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Thunderbird is already running, but is not responding error message when starting TB

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  • Last reply by BillH

BillH
BillH
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I just got a new Windows 11 laptop. I installed TB 102.1.2 on it. I deleted the contents of the new profile that it created and then copied the contents of the old profile into the new one. All seems fine and all my accounts and local folders are there and working fine. I use IMAP.

The problem is that when I start TB sometimes I get an error saying "Thunderbird is already running, but is not responding. The old Thunderbird process must be closed to open a new window.". The problem is that there is no Thunderbird running already.

I read through some other posts here and found out about parent.lock. I deleted this and TB started up next time without the error. However when I closed TB and restarted it, I got the error again. This same scenario will result in the error message every time.

I tried uninstalling and reinstalling TB, but I still get the same error.

I tried creating a new profile and again copying over the contents of my old profile. I still get the error.

I saw some references to antivirus programs potentially being a problem. I closed my AV program and tried again, but I still got the same error.

I am running the same version of TB on several Windows 10 computers and don't have any problems.

Any ideas on what else I could try?

Thanks, Bill

I just got a new Windows 11 laptop. I installed TB 102.1.2 on it. I deleted the contents of the new profile that it created and then copied the contents of the old profile into the new one. All seems fine and all my accounts and local folders are there and working fine. I use IMAP. The problem is that when I start TB sometimes I get an error saying "Thunderbird is already running, but is not responding. The old Thunderbird process must be closed to open a new window.". The problem is that there is no Thunderbird running already. I read through some other posts here and found out about parent.lock. I deleted this and TB started up next time without the error. However when I closed TB and restarted it, I got the error again. This same scenario will result in the error message every time. I tried uninstalling and reinstalling TB, but I still get the same error. I tried creating a new profile and again copying over the contents of my old profile. I still get the error. I saw some references to antivirus programs potentially being a problem. I closed my AV program and tried again, but I still got the same error. I am running the same version of TB on several Windows 10 computers and don't have any problems. Any ideas on what else I could try? Thanks, Bill

Modified by BillH

All Replies (1)

BillH
BillH Question owner
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A bit more info...

On my Win 11 tablet I started TB after deleting parent.lock. I looked in File Explorer and saw the parent.lock file in my profile. I then closed TB and the parent.lock file was not deleted. After reading some other posts I got the impression that it was supposed to be deleted when TB was closed. When I restart TB I get the error.

I then went to my two Win 10 computers and looked and the same is actually true. When TB is closed the parent.lock file is not deleted. However, I do not get any error on these machines when I restart TB even though there is a parent.lock file in the profile.

So, maybe the parent.lock file isn't the problem? I'm really confused now.

Any help appreciated.

Thanks, Bill

Modified by BillH