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thunderbird won't start after installion

Beno

thunderbird won't start after installation giving message that a version is already running. I end the task in task manager and it doesn't help, then restart with same erro. I tried deleting the parent.lock file from the profile and that didn't help. What next? Has anyone solved this issue?

thunderbird won't start after installation giving message that a version is already running. I end the task in task manager and it doesn't help, then restart with same erro. I tried deleting the parent.lock file from the profile and that didn't help. What next? Has anyone solved this issue?

All Replies (2)

Beno said

Has anyone solved this issue?

Perhaps you need to ask has anyone else even seen this issue!

You appear to be using Thunderbird on Window 10 or 11 but do you have an antivirus product that might include a software firewall?

Do you get any further if you hold the right shift key while you start Thunderbird?

Matt, Thanks for reply. I am on W11 and am using Windows Defender as my anti-virus not a commercial 3rd party, like McAfee or Norton. I have tried uninstalling/reinstalling with no success, that is, same issue. I tried starting while holding the right shift as suggested with the same error coming up. I saw an AI response when I Googled this condition (last wee) that suggested deleting the parent.lock file in the profile, which I also tried with no success. I have used Thunderbird for years and am saddened that I can't solve this issue that will necessitate my moving to another client. thanks again in advance if you have any further ideas. Beno