diff --git a/cli/mad/main.go b/cli/mad/main.go
index 5a84a0e..f9ef2b0 100644
--- a/cli/mad/main.go
+++ b/cli/mad/main.go
@@ -15,7 +15,7 @@ import (
 func main() {
 	app := cli.NewApp()
 	app.Name = "Mad"
-	app.Version = "20210401"
+	app.Version = "20240102"
 	app.Usage = "Generate root CA and derivative certificate for any domains and any IPs"
 	app.Authors = []*cli.Author{
 		{
diff --git a/install.go b/install.go
index faa0377..fb7812e 100644
--- a/install.go
+++ b/install.go
@@ -1,10 +1,20 @@
-// +build !darwin
-// +build !windows
+//go:build !darwin && !windows
 
 package mad
 
 import "errors"
 
 func Install(ca string) error {
-	return errors.New("Unsupported your OS, PR welcome, https://github.com/txthinking/mad")
+	return errors.New(`
+We cannot automate the certificate installation for you.
+Different Linux distributions have different installation methods, the following is an example for Ubuntu:
+
+https://ubuntu.com/server/docs/security-trust-store
+
+sudo apt-get install -y ca-certificates
+sudo cp ~/.nami/bin/ca.pem /usr/local/share/ca-certificates/ca.crt
+sudo update-ca-certificates
+
+If you are using a different distribution, please refer to the relevant official documentation.
+`)
 }