No synchronisation between em Client and Google Calendar

I am using em Client (em Client Ver.: 9.1.2109) for years to my satisfaction, among other things to synchronise my appointments between my PC (-> em Client Calendar) and my smartphone (aCalendar) via Google Calendar.
About two weeks ago, the synchronisation between PC and Google Calendar stopped working; the synchronisation between smartphone and Google Calendar continues.

I installed em client (and data backup) on a second (similar) computer, with the result that synchronisation occurs properly.

On the first computer, I uninstalled em Client and reinstalled it, as well as uploading the data backup.

The result: still no synchronisation between PC and Google Calendar. I can see from the log files (please see attached files) that the authentication is aborted, but I lack the insider knowledge to recognise the reason for this.

I have also not found a solution in the support (e.g. “Gmail won’t load or sync”).

I request you to help me in troubleshooting.

File “auth” (with modified email-adress):
16:20:59.887|00C| eM Client 9.1.2109+9967b9369e (Windows)
16:21:03.105|023| ReacquireCredentials_Oauth_AccessToken]()
16:21:03.105|023| Access Token = Expiration = 01.01.0001 00:00:00
16:21:03.105|023| Refresh Token = 1//09VQYabJviitjCgYIARAAGAkSNwF-L9IrE00jP5wU-hJRvzWQqaVeXBer2jdyrEa6hFdwf4YGmpm55TVa5gps1ffhqBuVOGIwbYw
16:21:03.105|020| ReacquireCredentials_Oauth_AccessToken]()
16:21:03.105|020| Access Token = Expiration = 01.01.0001 00:00:00
16:21:03.106|020| Refresh Token = 1//09VQYabJviitjCgYIARAAGAkSNwF-L9IrE00jP5wU-hJRvzWQqaVeXBer2jdyrEa6hFdwf4YGmpm55TVa5gps1ffhqBuVOGIwbYw
16:21:03.112|009| RefreshAccessToken]()
16:21:03.287|009| RefreshAccessToken]()
16:21:03.373|023| ReacquireCredentials_Oauth_AccessToken]() = Abort
16:21:03.373|023| Access Token = Expiration = 01.01.0001 00:00:00
16:21:03.373|020| ReacquireCredentials_Oauth_AccessToken]() = Abort
16:21:03.373|020| Access Token = Expiration = 01.01.0001 00:00:00

File “ Google calendar”
16:21:03.050|009| eM Client 9.1.2109+9967b9369e (Windows)
16:21:03.050|009| Account’s UID is 11ee06ce-fa92-4dcf-baf2-acac97962aac
16:21:03.050|009| AccountBase.ChangeOnlineState : State changed to ONLINE due User
16:21:03.382|020| Exception: MailClient.Accounts.AuthenticationAbortedException: Authentifizierung abgebrochen
16:21:03.382|020| at MailClient.Protocols.Gdata.GenericGapiCommand.Execute(WorkerStatus status)
16:21:03.382|020| at MailClient.Commands.Command.Process(WorkerStatus status)
16:21:03.384|00F| AccountBase.ChangeOnlineState : State changed to OFFLINE due LoginCanceled

File “ Google Settings”
16:21:03.050|010| eM Client 9.1.2109+9967b9369e (Windows)
16:21:03.050|010| Account’s UID is 11ee06ce-fa92-4dcf-baf2-acac97962aac
16:21:03.050|010| AccountBase.ChangeOnlineState : State changed to ONLINE due User
16:21:03.382|023| Exception: MailClient.Accounts.AuthenticationAbortedException: Authentifizierung abgebrochen
16:21:03.382|023| at MailClient.Protocols.Gdata.GenericGapiCommand.Execute(WorkerStatus status)
16:21:03.382|023| at MailClient.Commands.Command.Process(WorkerStatus status)
16:21:03.384|010| AccountBase.ChangeOnlineState : State changed to OFFLINE due LoginCanceled

Try Repairing the Google Calendar in eM Client.

Click the Calendar icon at the bottom left of eM Client.


Then “Right click” your “Gmail Calendar” and “Click Properties” at the bottom

Next click the “Repair” tab at the top and finally click “Repair”. This will take time as eM Client has to rebuild the local calendar cache etc

If the Google Calendar still won’t sync in eM Client to your online calendar, I would then remove the whole Google account in eM Client and then Re-add your Google account "via the automatic wizard at the top via “Menu / Accounts”. Before removing first backup eM Client via “Menu / Backup”. You can see when the backup is completed via “Menu / Operations”.

Note:- Also recommend “to remove the eM Client token” in your Online Google Security “Third Party allowed apps allowed apps” sections “before readding your Google account” so its all new.

Security (

The above procedure didn’t help.
I continued to test without the firewall and the virus programme, again without success.

Are there any other measures to restore the authentication?