diff --git a/imio/dms/mail/browser/actionspanel.py b/imio/dms/mail/browser/actionspanel.py
index a8bfe21c8..fe433d9fb 100644
--- a/imio/dms/mail/browser/actionspanel.py
+++ b/imio/dms/mail/browser/actionspanel.py
@@ -106,7 +106,7 @@ def assignable_users(self):
 
     def sortTransitions(self, lst):
         """Sort transitions following transitions list order"""
-        lst.sort(lambda x, y: cmp(self.tr_order.get(x["id"], 99), self.tr_order.get(y["id"], 99)))
+        lst.sort(lambda x, y: cmp(self.tr_order.get(x["id"], 99), self.tr_order.get(y["id"], 99)))  # noqa F821
 
     @ram.cache(actionspanelview_cachekey)
     def DmsIMActionsPanelView__call__(
@@ -183,6 +183,7 @@ def __init__(self, context, request):
         # self.ACCEPTABLE_ACTIONS = ['copy', 'paste', 'delete']
         self.ACCEPTABLE_ACTIONS = ["delete"]
         self.SECTIONS_TO_RENDER += (
+            "render_duplicate_button",
             "render_create_from_template_button",
             "render_create_new_message",
             "render_send_email",
@@ -190,7 +191,7 @@ def __init__(self, context, request):
 
     def sortTransitions(self, lst):
         """Sort transitions following transitions list order"""
-        lst.sort(lambda x, y: cmp(self.tr_order[x["id"]], self.tr_order[y["id"]]))
+        lst.sort(lambda x, y: cmp(self.tr_order[x["id"]], self.tr_order[y["id"]]))  # noqa F821
 
     def may_create_from_template(self):
         """
@@ -207,6 +208,17 @@ def render_create_from_template_button(self):
             return ViewPageTemplateFile("templates/actions_panel_create_from_template.pt")(self)
         return ""
 
+    def may_duplicate(self):
+        """Method that check if special 'duplicate' action has to be displayed."""
+        if self.member.has_permission("Add portal content", self.portal["outgoing-mail"]):
+            return True
+        return False
+
+    def render_duplicate_button(self):
+        if self.may_duplicate():
+            return ViewPageTemplateFile("templates/actions_panel_duplicate.pt")(self)
+        return ""
+
     def may_create_new_message(self):
         if (
             self.context.is_email()
@@ -296,7 +308,7 @@ def __init__(self, context, request):
 
     def sortTransitions(self, lst):
         """Sort transitions following transitions list order"""
-        lst.sort(lambda x, y: cmp(self.tr_order[x["id"]], self.tr_order[y["id"]]))
+        lst.sort(lambda x, y: cmp(self.tr_order[x["id"]], self.tr_order[y["id"]]))  # noqa F821
 
     @ram.cache(actionspanelview_cachekey)
     def DmsTaskActionsPanelView__call__(
diff --git a/imio/dms/mail/browser/configure.zcml b/imio/dms/mail/browser/configure.zcml
index 80666ecfb..3a8bad4b6 100644
--- a/imio/dms/mail/browser/configure.zcml
+++ b/imio/dms/mail/browser/configure.zcml
@@ -18,6 +18,13 @@
         class=".views.CreateFromTemplateForm"
         />
 
+    <browser:page
+        name="om-duplicate"
+        for="imio.dms.mail.dmsmail.IImioDmsOutgoingMail"
+        permission="zope2.View"
+        class=".views.OMDuplicateForm"
+        />
+
     <browser:page
         name="imiodmsmail-settings"
         for="Products.CMFPlone.interfaces.IPloneSiteRoot"
diff --git a/imio/dms/mail/browser/settings.py b/imio/dms/mail/browser/settings.py
index 27ff38e4d..730e97bc4 100644
--- a/imio/dms/mail/browser/settings.py
+++ b/imio/dms/mail/browser/settings.py
@@ -295,6 +295,17 @@ class IStateSetSchema(IRuleSchema):
 #     ]
 # )
 
+omail_duplicate_fields = SimpleVocabulary(
+    [
+        SimpleTerm(value=u"category", title=_(u"Keep classification category")),
+        SimpleTerm(value=u"folder", title=_(u"Keep classification folder")),
+        SimpleTerm(value=u"reply_to", title=_(u"Keep reply_to mails")),
+        SimpleTerm(value=u"dms_files", title=_(u"Keep DMS files")),
+        SimpleTerm(value=u"annexes", title=_(u"Keep annexes")),
+        SimpleTerm(value=u"link_to_duplicated", title=_(u"Link to duplicated mail")),
+    ]
+)
+
 oemail_sender_email_values = SimpleVocabulary(
     [
         SimpleTerm(value=u"agent_email", title=_(u"Sender held position email is used")),
@@ -451,6 +462,8 @@ class IImioDmsMailConfig(model.Schema):
             "omail_fullname_used_form",
             "omail_send_modes",
             "omail_post_mailing",
+            "omail_duplicate_display_fields",
+            "omail_duplicate_true_default_values",
             "omail_fields",
             "omail_group_encoder",
         ],
@@ -505,6 +518,22 @@ class IImioDmsMailConfig(model.Schema):
         default=True,
     )
 
+    omail_duplicate_display_fields = schema.List(
+        title=_(u"Fields to display when duplicating an outgoing mail"),
+        required=False,
+        value_type=schema.Choice(vocabulary=omail_duplicate_fields),
+        default=[u"category", u"folder", u"reply_to", u"dms_files", u"annexes", u"link_to_duplicated"],
+    )
+    # widget("omail_duplicate_display_fields", CheckBoxFieldWidget, multiple="multiple", size=5)
+
+    omail_duplicate_true_default_values = schema.List(
+        title=_(u"Default values to True when duplicating an outgoing mail"),
+        description=_(u"If checked, the default value will be True."),
+        required=False,
+        value_type=schema.Choice(vocabulary=omail_duplicate_fields),
+        default=[u"category", u"folder", u"annexes"],
+    )
+
     omail_fields = schema.List(
         title=_(u"${type} fields display", mapping={"type": _("Outgoing mail")}),
         description=_(u"Configure this carefully. You can order with arrows."),
diff --git a/imio/dms/mail/browser/static/copy.svg b/imio/dms/mail/browser/static/copy.svg
new file mode 100644
index 000000000..b59068028
--- /dev/null
+++ b/imio/dms/mail/browser/static/copy.svg
@@ -0,0 +1,3 @@
+<svg xmlns="http://www.w3.org/2000/svg" width="16" height="16" fill="currentColor" class="bi bi-copy" viewBox="0 0 16 16">
+  <path fill-rule="evenodd" d="M4 2a2 2 0 0 1 2-2h8a2 2 0 0 1 2 2v8a2 2 0 0 1-2 2H6a2 2 0 0 1-2-2zm2-1a1 1 0 0 0-1 1v8a1 1 0 0 0 1 1h8a1 1 0 0 0 1-1V2a1 1 0 0 0-1-1zM2 5a1 1 0 0 0-1 1v8a1 1 0 0 0 1 1h8a1 1 0 0 0 1-1v-1h1v1a2 2 0 0 1-2 2H2a2 2 0 0 1-2-2V6a2 2 0 0 1 2-2h1v1z"/>
+</svg>
\ No newline at end of file
diff --git a/imio/dms/mail/browser/templates/actions_panel_duplicate.pt b/imio/dms/mail/browser/templates/actions_panel_duplicate.pt
new file mode 100644
index 000000000..b78000a89
--- /dev/null
+++ b/imio/dms/mail/browser/templates/actions_panel_duplicate.pt
@@ -0,0 +1,10 @@
+<td class="noPadding" i18n:domain="imio.dms.mail">
+  <a tal:attributes="href string:${context/absolute_url}/@@om-duplicate"
+     target="_parent"
+     class="overlay"
+     tal:define="dummy view/saveHasActions;">
+     <input tal:condition="not:view/useIcons" type="button" value="Duplicate" class="apButton apButtonAction apButtonAction_duplicate" i18n:attributes="value" />
+     <img tal:condition="view/useIcons" i18n:attributes="title" title="Duplicate outgoing mail" tal:attributes="src string: ${view/portal_url}/++resource++imio.dms.mail/copy.svg;"/>
+  </a>
+</td>
+<td class="noPadding">
diff --git a/imio/dms/mail/browser/views.py b/imio/dms/mail/browser/views.py
index e95e0ee3c..9720a46c0 100644
--- a/imio/dms/mail/browser/views.py
+++ b/imio/dms/mail/browser/views.py
@@ -6,6 +6,8 @@
 from imio.dms.mail import _
 from imio.dms.mail import _tr
 from imio.dms.mail import PMH_ENABLED
+from imio.dms.mail.browser.settings import IImioDmsMailConfig
+from imio.dms.mail.browser.settings import omail_duplicate_fields
 from imio.dms.mail.browser.table import CKTemplatesTable
 from imio.dms.mail.browser.table import PersonnelTable
 from imio.dms.mail.dmsfile import IImioDmsFile
@@ -19,11 +21,16 @@
 from imio.helpers.fancytree.views import BaseRenderFancyTree
 from imio.helpers.workflow import do_transitions
 from imio.helpers.xhtml import object_link
+from imio.pyutils.utils import safe_encode
 from plone import api
 from Products.CMFPlone.utils import safe_unicode
 from Products.Five import BrowserView
 from Products.PageTemplates.Expressions import SecureModuleImporter
 from unidecode import unidecode  # unidecode_expect_nonascii not yet available in used version
+from z3c.form import button
+from z3c.form.field import Fields
+from z3c.form.form import Form
+from zope import schema
 from zope.annotation import IAnnotations
 from zope.component import getMultiAdapter
 from zope.i18n import translate
@@ -70,6 +77,65 @@ def redirect_url(self, uid):
         return "{}/persistent-document-generation?{}".format(url, "&".join(params))
 
 
+class OMDuplicateForm(Form):
+
+    """Duplicate an outgoing mail."""
+    label = _(u"Duplicate mail")
+    ignoreContext = True
+
+    def update(self):
+        """Handle fields."""
+        om_fields = api.portal.get_registry_record("omail_fields", IImioDmsMailConfig, [])
+        om_fields = [dic["field_name"] for dic in om_fields]
+        matching = {u"category": "IClassificationFolder.classification_categories",
+                    u"folder": "IClassificationFolder.classification_folders",
+                    u"reply_to": "reply_to",
+                    u"link_to_duplicated": "reply_to"}
+        to_show = api.portal.get_registry_record("omail_duplicate_display_fields", IImioDmsMailConfig, [])
+        to_true = api.portal.get_registry_record("omail_duplicate_true_default_values", IImioDmsMailConfig, [])
+        for term in omail_duplicate_fields:
+            if ((term.value in matching and matching[term.value] not in om_fields) or
+                    (term.value not in to_show and term.value not in to_true)):
+                continue
+            self.fields += Fields(
+                schema.Bool(
+                    __name__=safe_encode(term.value),
+                    title=term.title,
+                    default=term.value in to_true,
+                ))
+        super(OMDuplicateForm, self).update()
+
+    def updateWidgets(self, prefix=None):
+        super(OMDuplicateForm, self).updateWidgets()
+
+        # we hide fields not to show
+        to_show = api.portal.get_registry_record("omail_duplicate_display_fields", IImioDmsMailConfig, [])
+        for term in omail_duplicate_fields:
+            if term.value not in to_show:
+                self.widgets[term.value].mode = "hidden"
+
+    @button.buttonAndHandler(_('Duplicate'), name='duplicate')
+    def handleApply(self, action):
+        data, errors = self.extractData()
+
+        if errors:
+            self.status = self.formErrorsMessage
+            return
+
+        # Duplicate the mail
+        odm_utils = getMultiAdapter((self.context, self.request), name="odm-utils")
+        duplicated_mail = odm_utils.duplicate(
+            keep_category=data.get('category', False),
+            keep_folder=data.get('folder', False),
+            keep_reply_to=data.get('reply_to', False),
+            keep_dms_files=data.get('dms_files', False),
+            keep_annexes=data.get('annexes', False),
+            link_to_duplicated=data.get('link_to_duplicated', False),
+        )
+
+        self.request.response.redirect(duplicated_mail.absolute_url()+"/edit")
+
+
 def parse_query(text):
     """Copied from plone.app.vocabularies.catalog.parse_query but cleaned."""
     for char in "?-+*()":
diff --git a/imio/dms/mail/skins/imio_dms_mail/imiodmsmail.css.dtml b/imio/dms/mail/skins/imio_dms_mail/imiodmsmail.css.dtml
index fe4c3b6bb..c8e515049 100644
--- a/imio/dms/mail/skins/imio_dms_mail/imiodmsmail.css.dtml
+++ b/imio/dms/mail/skins/imio_dms_mail/imiodmsmail.css.dtml
@@ -471,6 +471,10 @@ dl.portletWidgetCollection div.portlet_add_icons a {
     background-image: url('&dtml-portal_url;/++resource++imio.dms.mail/models_icon.png');
 }
 
+.apButtonAction_duplicate {
+    background-image: url('&dtml-portal_url;/++resource++imio.dms.mail/copy.svg');
+}
+
 .apButtonAction_sendemail {
     background-image: url('&dtml-portal_url;/++resource++imio.dms.mail/send_email.svg');
     background-size: 18px 18px;
diff --git a/imio/dms/mail/subscribers.py b/imio/dms/mail/subscribers.py
index 2390c21ff..d7eca2495 100644
--- a/imio/dms/mail/subscribers.py
+++ b/imio/dms/mail/subscribers.py
@@ -72,6 +72,7 @@
 # from zope.component.interfaces import ComponentLookupError
 from zope.annotation import IAnnotations
 from zope.component import getAdapter
+from zope.component import getMultiAdapter
 from zope.component import getSiteManager
 from zope.component import getUtility
 from zope.component import queryUtility
@@ -384,6 +385,16 @@ def dmsoutgoingmail_transition(mail, event):
         mail.portal_catalog.reindexObject(mail, idxs=("in_out_date",), update_metadata=0)
 
 
+def dmsoutgoingmail_modified(mail, event):
+    annot = IAnnotations(mail).get('imio.dms.mail', {})
+    copy_dms_files_from = annot.get('copy_dms_files_from')
+    if copy_dms_files_from:
+        del annot['copy_dms_files_from']
+        original_mail = uuidToObject(copy_dms_files_from, unrestricted=True)
+        odm_utils = getMultiAdapter((mail, mail.REQUEST), name="odm-utils")
+        odm_utils.copy_dms_files(original_mail)
+
+
 def dv_handle_file_creation(obj, event):
     """Intermediate function to avoid converting some files in documentviewer"""
     if obj.portal_type in DV_AVOIDED_TYPES:
diff --git a/imio/dms/mail/subscribers.zcml b/imio/dms/mail/subscribers.zcml
index 7e357c39f..bde5b4cb2 100644
--- a/imio/dms/mail/subscribers.zcml
+++ b/imio/dms/mail/subscribers.zcml
@@ -98,6 +98,12 @@
         handler=".subscribers.dmsoutgoingmail_transition"
       />
 
+    <subscriber
+        for="imio.dms.mail.dmsmail.IImioDmsOutgoingMail
+            zope.lifecycleevent.interfaces.IObjectModifiedEvent"
+        handler=".subscribers.dmsoutgoingmail_modified"
+      />
+
     <!-- Various -->
     <subscriber
         for="plone.dexterity.interfaces.IDexterityContent
diff --git a/imio/dms/mail/tests/test_utils.py b/imio/dms/mail/tests/test_utils.py
index 6d8a6aaea..0aa61418e 100644
--- a/imio/dms/mail/tests/test_utils.py
+++ b/imio/dms/mail/tests/test_utils.py
@@ -25,6 +25,7 @@
 from imio.dms.mail.utils import IdmUtilsMethods
 from imio.dms.mail.utils import invalidate_users_groups
 from imio.dms.mail.utils import list_wf_states
+from imio.dms.mail.utils import OdmUtilsMethods
 from imio.dms.mail.utils import PREVIEW_DIR
 from imio.dms.mail.utils import set_dms_config
 from imio.dms.mail.utils import sub_create
@@ -44,6 +45,7 @@
 from Products.CMFPlone.utils import base_hasattr
 from z3c.relationfield.relation import RelationValue
 from zope.annotation.interfaces import IAnnotations
+from zope.component import getMultiAdapter
 from zope.component import getUtility
 from zope.intid.interfaces import IIntIds
 
@@ -759,6 +761,182 @@ def test_IdmUtilsMethods_proposed_to_n_plus_col_cond0(self):
         self.assertFalse("searchfor_proposed_to_n_plus_1" in im_folder)
         self.assertTrue("See test_wfadaptations_imservicevalidation.py")
 
+    def test_OdmUtilsMethods_duplicate(self):
+        intids = getUtility(IIntIds)
+
+        omail2 = sub_create(
+            self.portal["outgoing-mail"],
+            "dmsoutgoingmail",
+            datetime.now(),
+            "my-id2",
+            title="My title",
+            description="Description",
+            send_modes=["post"],
+            classification_folders=[self.portal.folders['ordre-public-reglement-general-de-police'].UID()],
+            classification_categories=self.portal.folders['ordre-public-reglement-general-de-police'].classification_categories,
+        )
+
+        omail = sub_create(
+            self.portal["outgoing-mail"],
+            "dmsoutgoingmail",
+            datetime.now(),
+            "my-id",
+            title="My title",
+            description="Description",
+            treating_groups=self.pgof["direction-generale"]["secretariat"].UID(),
+            send_modes=["post"],
+            classification_folders=[self.portal.folders['ordre-public-reglement-general-de-police'].UID()],
+            classification_categories=self.portal.folders['ordre-public-reglement-general-de-police'].classification_categories,
+            reply_to=[RelationValue(intids.getId(omail2))],
+        )
+        createContentInContainer(omail, "dmsommainfile", title=u"D001", file=NamedBlobFile(filename=u"scanned.pdf"))
+        createContentInContainer(
+            omail, "dmsappendixfile", title=u"A001", file=NamedBlobFile(filename=u"appendix.odt")
+        )
+        view = OdmUtilsMethods(omail, omail.REQUEST)
+
+        duplicated_mail = view.duplicate(
+            keep_category=True,
+            keep_folder=True,
+            keep_reply_to=True,
+            keep_dms_files=True,
+            keep_annexes=True,
+            link_to_duplicated=True,
+        )
+        self.assertEqual(duplicated_mail.title, u"My title")
+        self.assertEqual(duplicated_mail.description, u"Description")
+        self.assertEqual(duplicated_mail.send_modes, ["post"])
+        self.assertGreater(duplicated_mail.creation_date, omail.creation_date)
+        self.assertNotEqual(duplicated_mail.internal_reference_no, omail.internal_reference_no)
+        self.assertIsNone(duplicated_mail.mail_date)
+        self.assertIsNone(duplicated_mail.due_date)
+        self.assertIsNone(duplicated_mail.outgoing_date)
+
+        # Test keep_category
+        self.assertEqual(duplicated_mail.classification_categories, self.portal.folders['ordre-public-reglement-general-de-police'].classification_categories)
+        # Test keep_folder
+        self.assertEqual(duplicated_mail.classification_folders, [self.portal.folders['ordre-public-reglement-general-de-police'].UID()])
+        # Test keep_linked_mails
+        self.assertEqual(len(duplicated_mail.reply_to), 2)
+        self.assertEqual(omail2, duplicated_mail.reply_to[0].to_object)
+        # Test keep_dms_files
+        self.assertNotIn("d001", duplicated_mail)  # By default, we never keep not generated main files
+        # Test keep_annexes
+        self.assertIn("a001", duplicated_mail)
+        # Test link_to_original
+        self.assertEqual(omail, duplicated_mail.reply_to[1].to_object)
+
+        # Test not keeping categories
+        duplicated_mail = view.duplicate(
+            keep_category=False,
+            keep_folder=True,
+            keep_reply_to=True,
+            keep_dms_files=True,
+            keep_annexes=True,
+            link_to_duplicated=True,
+        )
+        self.assertIsNone(duplicated_mail.classification_categories)
+
+        # Test not keeping folders
+        duplicated_mail = view.duplicate(
+            keep_category=True,
+            keep_folder=False,
+            keep_reply_to=True,
+            keep_dms_files=True,
+            keep_annexes=True,
+            link_to_duplicated=True,
+        )
+        self.assertIsNone(duplicated_mail.classification_folders)
+
+        # Test not keeping linked mails
+        duplicated_mail = view.duplicate(
+            keep_category=True,
+            keep_folder=True,
+            keep_reply_to=False,
+            keep_dms_files=True,
+            keep_annexes=True,
+            link_to_duplicated=True,
+        )
+        self.assertEqual(len(duplicated_mail.reply_to), 1)
+        self.assertNotEqual(omail2, duplicated_mail.reply_to[0].to_object)
+
+        # Test not keeping dms files
+        duplicated_mail = view.duplicate(
+            keep_category=True,
+            keep_folder=True,
+            keep_reply_to=True,
+            keep_dms_files=False,
+            keep_annexes=True,
+            link_to_duplicated=True,
+        )
+        self.assertNotIn("d001", duplicated_mail)
+
+        # Test not keeping annexes
+        duplicated_mail = view.duplicate(
+            keep_category=True,
+            keep_folder=True,
+            keep_reply_to=True,
+            keep_dms_files=True,
+            keep_annexes=False,
+            link_to_duplicated=True,
+        )
+        self.assertNotIn("a001", duplicated_mail)
+
+        # Test not linking to original
+        duplicated_mail = view.duplicate(
+            keep_category=True,
+            keep_folder=True,
+            keep_reply_to=True,
+            keep_dms_files=True,
+            keep_annexes=True,
+            link_to_duplicated=False,
+        )
+        self.assertEqual(len(duplicated_mail.reply_to), 1)
+        self.assertNotEqual(omail, duplicated_mail.reply_to[0].to_object)
+
+        # Test with generated main files
+        generation_view = getMultiAdapter((omail, omail.REQUEST), name="persistent-document-generation")
+        pod_template = self.portal.templates["om"]["main"]
+        generation_view.pod_template = pod_template
+        generation_view.output_format = 'odt'
+        generation_view.generate_persistent_doc(pod_template, 'odt')
+        duplicated_mail = view.duplicate(
+            keep_category=True,
+            keep_folder=True,
+            keep_reply_to=True,
+            keep_dms_files=True,
+            keep_annexes=True,
+            link_to_duplicated=True,
+        )
+        self.assertIn('012999900000002', duplicated_mail)
+        dms_file = duplicated_mail['012999900000002']
+        annot = IAnnotations(dms_file)['documentgenerator']
+        self.assertEqual(annot['template_uid'], pod_template.UID())
+
+        # Test with mailings (publipostage)
+        omail.recipients = [RelationValue(intids.getId(self.contacts["jeancourant"]["agent-electrabel"])), RelationValue(intids.getId(self.contacts["sergerobinet"]["agent-swde"]))]
+        generation_view.generate_persistent_doc(pod_template, 'odt')
+        mailing_loop_generation_view = getMultiAdapter((omail, omail.REQUEST), name="mailing-loop-persistent-document-generation")
+        mailing_loop_pod_template = self.portal.templates["om"]["mailing"]
+        mailing_loop_generation_view.orig_template = pod_template
+        mailing_loop_generation_view.pod_template = mailing_loop_pod_template
+        mailing_loop_generation_view.output_format = 'odt'
+        mailing_loop_generation_view.document = omail['012999900000001']
+        mailing_loop_generation_view.generate_persistent_doc(mailing_loop_pod_template, 'odt')
+        duplicated_mail = view.duplicate(
+            keep_category=True,
+            keep_folder=True,
+            keep_reply_to=True,
+            keep_dms_files=True,
+            keep_annexes=True,
+            link_to_duplicated=True,
+        )
+        self.assertEqual(duplicated_mail.keys(), ['a001', '012999900000004'])
+        dms_file = duplicated_mail['012999900000004']
+        annot = IAnnotations(dms_file)['documentgenerator']
+        self.assertEqual(annot['template_uid'], pod_template.UID())
+        self.assertTrue(annot['need_mailing'])
+
     def test_create_period_folder(self):
         dte = datetime.now() - timedelta(days=7)
         foldername = dte.strftime("%Y%U")  # week
diff --git a/imio/dms/mail/tests/test_views.py b/imio/dms/mail/tests/test_views.py
index 71192b359..52527ea62 100644
--- a/imio/dms/mail/tests/test_views.py
+++ b/imio/dms/mail/tests/test_views.py
@@ -7,11 +7,19 @@
 from imio.dms.mail.browser.views import parse_query
 from imio.dms.mail.testing import change_user
 from imio.dms.mail.testing import DMSMAIL_INTEGRATION_TESTING
+from imio.dms.mail.utils import sub_create
 from imio.helpers.content import get_object
 from imio.helpers.content import richtextval
 from imio.helpers.emailer import get_mail_host
+from imio.helpers.test_helpers import ImioTestHelpers
+from mock import patch
 from plone import api
+from plone.dexterity.utils import createContentInContainer
+from plone.namedfile import NamedBlobFile
+from z3c.relationfield.relation import RelationValue
+from zope.component import getUtility
 from zope.i18n import translate
+from zope.intid.interfaces import IIntIds
 
 import json
 import unittest
diff --git a/imio/dms/mail/utils.py b/imio/dms/mail/utils.py
index 38b6f1b6b..840aa66ce 100644
--- a/imio/dms/mail/utils.py
+++ b/imio/dms/mail/utils.py
@@ -3,6 +3,8 @@
 from collective.behavior.talcondition.utils import _evaluateExpression
 from collective.contact.plonegroup.config import get_registry_organizations
 from collective.contact.plonegroup.utils import organizations_with_suffixes
+from collective.dms.basecontent.dmsfile import IDmsAppendixFile
+from collective.documentgenerator.content.pod_template import IMailingLoopTemplate
 from collective.documentviewer.convert import Converter
 from collective.documentviewer.convert import saveFileToBlob
 from collective.eeafaceted.collectionwidget.utils import _updateDefaultCollectionFor
@@ -20,6 +22,7 @@
 from imio.dms.mail import MAIN_FOLDERS
 from imio.dms.mail import PERIODS
 from imio.dms.mail import PRODUCT_DIR
+from imio.dms.mail.dmsfile import IImioDmsFile
 from imio.dms.mail.interfaces import IProtectedItem
 from imio.helpers.batching import batch_delete_files
 from imio.helpers.batching import batch_get_keys
@@ -36,6 +39,7 @@
 from imio.helpers.content import object_values
 from imio.helpers.content import uuidToObject
 from imio.helpers.security import check_zope_admin
+from imio.helpers.transmogrifier import get_correct_id
 from imio.helpers.workflow import do_transitions
 from imio.helpers.xhtml import object_link
 from interfaces import IIMDashboard
@@ -63,6 +67,7 @@
 from zc.relation.interfaces import ICatalog
 from zExceptions import Redirect
 from zope.annotation.interfaces import IAnnotations
+from zope.component import getMultiAdapter
 from zope.component import getUtility
 from zope.component.hooks import getSite
 from zope.interface import alsoProvides
@@ -1184,6 +1189,92 @@ def scanned_col_cond(self):
         """Condition for searchfor_scanned collection"""
         return self.is_in_user_groups(["encodeurs", "expedition"], admin=False, suffixes=[CREATING_GROUP_SUFFIX])
 
+    def duplicate(self, keep_category, keep_folder, keep_reply_to, keep_dms_files, keep_annexes, link_to_duplicated):
+        original_mail = self.context
+        pc = api.portal.get_tool("portal_catalog")
+        duplicated_mail = sub_create(
+            api.portal.get()["outgoing-mail"],
+            "dmsoutgoingmail",
+            datetime.now(),
+            get_correct_id([om.getId for om in pc(portal_type="dmsoutgoingmail")], original_mail.getId()),
+            title=original_mail.title,
+            description=original_mail.description,
+            recipients=original_mail.recipients[:] if original_mail.recipients else None,
+            treating_groups=original_mail.treating_groups[:] if original_mail.treating_groups else None,
+            assigned_user=original_mail.assigned_user,
+            sender=original_mail.sender,
+            recipient_groups=original_mail.recipient_groups[:] if original_mail.recipient_groups else None,
+            send_modes=original_mail.send_modes[:] if original_mail.send_modes else None,
+            task_description=original_mail.task_description,
+        )
+
+        if keep_category and hasattr(original_mail, 'classification_categories') and original_mail.classification_categories:
+            duplicated_mail.classification_categories = original_mail.classification_categories[:]
+        else:
+            duplicated_mail.classification_categories = None
+
+        if keep_folder and hasattr(original_mail, 'classification_folders') and original_mail.classification_folders:
+            duplicated_mail.classification_folders = original_mail.classification_folders[:]
+        else:
+            duplicated_mail.classification_folders = None
+
+        if keep_reply_to and hasattr(original_mail, 'reply_to') and original_mail.reply_to:
+            duplicated_mail.reply_to = original_mail.reply_to[:]
+
+        if keep_dms_files:
+            # Add an annotation to copy DMS files only after next edit
+            annot = IAnnotations(duplicated_mail)
+            annot.setdefault('imio.dms.mail', PersistentDict())  # make sure the key exists
+            annot['imio.dms.mail']['copy_dms_files_from'] = original_mail.UID()
+
+        if keep_annexes:
+            annexes = [sub_content.getId() for sub_content in original_mail.values() if IDmsAppendixFile.providedBy(sub_content)]
+            if annexes:
+                clipboard = original_mail.manage_copyObjects(annexes)
+                duplicated_mail.manage_pasteObjects(clipboard)
+
+        if link_to_duplicated:
+            intids = getUtility(IIntIds)
+            rel_id = intids.getId(original_mail)
+            if duplicated_mail.reply_to is None:
+                duplicated_mail.reply_to = []
+            duplicated_mail.reply_to.append(RelationValue(rel_id))
+
+        return duplicated_mail
+
+    def copy_dms_files(self, original_mail):
+        """Re-generate DMS files on this mail based on the templates used in the original mail."""
+        dms_files = [sub_content for sub_content in original_mail.values() if sub_content.portal_type == self.mainfile_type]
+        used_template_uids = set()
+        for dms_file in dms_files:
+            annot = IAnnotations(dms_file).get('documentgenerator', {})
+
+            # Skip if document was not generated (could be scanned)
+            if not annot:
+                continue
+
+            # Skip if document was already generated from the same template
+            if annot.get('template_uid') in used_template_uids:
+                continue
+
+            # Skip if document is final step of a mailing
+            document_generation_helper_view = getMultiAdapter((self.context, self.request), name="document_generation_helper_view")
+            requires_mailing = len(document_generation_helper_view.mailing_list()) > 1
+            if requires_mailing and not annot.get('need_mailing'):
+                continue
+
+            # Generate a new document from the same template
+            template_uid = annot.get('template_uid')
+            generation_view = getMultiAdapter((self.context, self.request), name="persistent-document-generation")
+            pod_template = generation_view.get_pod_template(template_uid)
+            # Skip if it's a mailing loop template
+            if IMailingLoopTemplate.providedBy(pod_template):
+                continue
+            generation_view.pod_template = pod_template
+            generation_view.output_format = 'odt'
+            generation_view.generate_persistent_doc(pod_template, 'odt')
+            used_template_uids.add(template_uid)
+
 
 class Dummy(object):
     """dummy class that allows setting attributes"""