Error-Communication With Previous Instance


I am getting the “Communication with the previous instance failed. The other instance has to be ended in order to start the application” error popup. I am running version 8.2.1237(b402cf3) on Windows 10, latest patch updates.

I searched the forums, and did the following to troubleshoot it:

  • Made sure eM Client is not running in task manager. I know it’s called “mailclient.exe”
  • Download the latest and repaired my install, the repair ended prematurely, nothing in Window’s error log.
  • Uninstalled and re-installed.
  • Unchecked “Use system notifications” in settings.

I seem to be getting them when I dismiss calendar events that are showing a notification when eM Client starts. I use Google Calendar, and Gmail.

No other mail or calendar programs are running on my computer.

What can I do to help troubleshoot this? I have reached the limit of my (limited) expertise. Thank you.

Sounds like you have an issue somewhere with eM Client program on your computer as normally closing the Mailclient.exe (in the task manager) and / or EMC (in the tray) will fix the issue.

If you have recently done a .zip backup of EMC via “Menu / Backup” (before this issue happened), try restoring via “Menu / File / Restore” and reboot your computer. Sometimes a restore will fix it.

Failing that as its a Google IMAP account , I would then uninstall eM Client and then manually delete eM Client (hidden) roaming folder. C:\Users\Yournamel\AppData\Roaming\eM Client and also check that the following eM Client folder is also deleted from C:\Program Files (x86)\eM Client . Then reinstall the same version of eM Client from the version history page -

If still the same issue disable everything in the “Startup Tab” in Windows to test, and reboot incase there is multiple instances of eM Client in there or something else causing this issue in the startup. Failing that you may need to do a eg: Registry scan of Windows etc or a pc tech to look at it.