diff --git a/idp/downloader.cpp b/idp/downloader.cpp
index f326a69..a7d041e 100644
--- a/idp/downloader.cpp
+++ b/idp/downloader.cpp
@@ -685,8 +685,8 @@ void Downloader::updateSpeed(NetFile *file, Timer *timer)
 {
     if(ui)
     {
-        double speed = (double)file->bytesDownloaded / ((double)timer->totalElapsed() / 1000.0);
-        double rtime = (double)(filesSize - (downloadedFilesSize + file->bytesDownloaded)) / speed * 1000.0;
+        double speed = (double)file->bytesDownloaded / nonzero((double)timer->totalElapsed() / 1000.0);
+        double rtime = (double)(filesSize - (downloadedFilesSize + file->bytesDownloaded)) / nonzero(speed) * 1000.0;
         
         if((filesSize == FILE_SIZE_UNKNOWN) || ((downloadedFilesSize + file->bytesDownloaded) > filesSize))
             ui->setSpeedInfo(f2i(speed));
diff --git a/idp/ui.cpp b/idp/ui.cpp
index 9f338dd..1aefb97 100644
--- a/idp/ui.cpp
+++ b/idp/ui.cpp
@@ -79,13 +79,13 @@ void Ui::setProgressInfo(DWORDLONG totalSize, DWORDLONG totalDownloaded, DWORDLO
 {
     if(!(totalSize == FILE_SIZE_UNKNOWN))
     {
-        double totalPercents = 100.0 / ((double)totalSize / (double)totalDownloaded);
+        double totalPercents = 100.0 / nonzero((double)totalSize / i2d(totalDownloaded));
         setProgressBarPos(controls["TotalProgressBar"], f2i(totalPercents));
     }
 
     if(!(fileSize == FILE_SIZE_UNKNOWN))
     {
-        double filePercents  = 100.0 / ((double)fileSize / (double)fileDownloaded);
+        double filePercents  = 100.0 / nonzero((double)fileSize / i2d(fileDownloaded));
         setProgressBarPos(controls["FileProgressBar"], f2i(filePercents));
     }
 }
diff --git a/idp/ui.h b/idp/ui.h
index 00e9001..ad29c2f 100644
--- a/idp/ui.h
+++ b/idp/ui.h
@@ -61,5 +61,7 @@ class Ui
 HWND uiMainWindow();
 
 #define f2i(x) (_isnan(x) ? 0 : (int)(x))
+#define i2d(x) ((x == 0) ? FLT_MIN : (double)x)
+#define nonzero(x) ((x == 0.0) ? FLT_MIN : (double)x)
 
 extern "C" void idpReportError();