This issue appear to be caused usually by McAfee. Are you one of their users?

Another possibility is Avast https://bugzilla.mozilla.org/show_bug.cgi?id=1791719#c3 If you still have trouble... 1. Do Settings > General > type "config" into the search 2. Open Config Editor 3. Search for "app.update.log" and set it to "true". 4. Restart Thunderbird. 5. Do Help > About 6. Open Tools > Developer Tools > Error Console 7. Type AUS into the filter 8. Copy everything starting with "AUS:" 9. Please paste the information here.

I have this problem. Here is my error dump as above

15 hidden AUS:SVC UpdateManager:_loadXMLFileIntoArray - XML file does not exist. path: C:\ProgramData\Mozilla-1de4eec8-1241-4177-a864-e594e8d1fb38\updates\8216C80C92C4E828\active-update.xml AUS:SVC Creating UpdateService AUS:SVC Logging current UpdateService status: AUS:SVC UpdateService.canUsuallyCheckForUpdates - able to check for updates AUS:SVC UpdateService.canCheckForUpdates - able to check for updates AUS:SVC getCanApplyUpdates - testing write access C:\ProgramData\Mozilla-1de4eec8-1241-4177-a864-e594e8d1fb38\updates\8216C80C92C4E828\update.test AUS:SVC isServiceInstalled - returning true AUS:SVC shouldUseService - returning true AUS:SVC getCanApplyUpdates - bypass the write checks because the Windows Maintenance Service can be used AUS:SVC isServiceInstalled - returning true AUS:SVC shouldUseService - returning true AUS:SVC getCanStageUpdates - able to stage updates using the service AUS:SVC Elevation required: false AUS:SVC Other instance of the application currently running: false AUS:SVC Downloading: false AUS:SVC End of UpdateService status AUS:SVC isServiceInstalled - returning true AUS:SVC shouldUseService - returning true AUS:SVC getCanStageUpdates - able to stage updates using the service AUS:SVC isServiceInstalled - returning true AUS:SVC shouldUseService - returning true AUS:SVC getCanStageUpdates - able to stage updates using the service AUS:SVC Checker: checkForUpdates, force: true AUS:SVC Creating UpdateService AUS:SVC Logging current UpdateService status: AUS:SVC UpdateService.canUsuallyCheckForUpdates - able to check for updates AUS:SVC UpdateService.canCheckForUpdates - able to check for updates AUS:SVC getCanApplyUpdates - testing write access C:\ProgramData\Mozilla-1de4eec8-1241-4177-a864-e594e8d1fb38\updates\8216C80C92C4E828\update.test AUS:SVC isServiceInstalled - returning true AUS:SVC shouldUseService - returning true AUS:SVC getCanApplyUpdates - bypass the write checks because the Windows Maintenance Service can be used AUS:SVC isServiceInstalled - returning true AUS:SVC shouldUseService - returning true AUS:SVC getCanStageUpdates - able to stage updates using the service AUS:SVC Elevation required: false AUS:SVC Other instance of the application currently running: false AUS:SVC Downloading: false AUS:SVC End of UpdateService status AUS:SVC UpdateService.canUsuallyCheckForUpdates - able to check for updates AUS:SVC UpdateService.canCheckForUpdates - able to check for updates AUS:SVC waitForOtherInstances - beginning polling AUS:SVC waitForOtherInstances - no other instances found, exiting AUS:SVC Checker:getUpdateURL - update URL: https://aus.thunderbird.net/update/6/Thunderbird/102.3.1/20220928170044/WINNT_x86_64-msvc-x64/en-GB/release/Windows_NT%2010.0.0.0.22000.978%20(x64)/ISET:SSE4_2,MEM:16320/default/default/update.xml?force=1 AUS:SVC Checker:checkForUpdates - sending request to: https://aus.thunderbird.net/update/6/Thunderbird/102.3.1/20220928170044/WINNT_x86_64-msvc-x64/en-GB/release/Windows_NT%2010.0.0.0.22000.978%20(x64)/ISET:SSE4_2,MEM:16320/default/default/update.xml?force=1 AUS:SVC Checker:onLoad - request completed downloading document AUS:SVC Checker:onLoad - Getting sslStatus failed. AUS:SVC Checker:onLoad - there was a problem checking for updates. Exception: TypeError: this._request.responseXML is null AUS:SVC Checker:onLoad - request.status: 302 AUS:SVC getStatusTextFromCode - transfer error: Update XML file not found (404), default code: 404 AUS:SVC UpdateService:removeDownloadListener - Warning: Didn't remove non-existent listener AUS:SVC getCanApplyUpdates - testing write access C:\ProgramData\Mozilla-1de4eec8-1241-4177-a864-e594e8d1fb38\updates\8216C80C92C4E828\update.test AUS:SVC isServiceInstalled - returning true AUS:SVC shouldUseService - returning true AUS:SVC getCanApplyUpdates - bypass the write checks because the Windows Maintenance Service can be used AUS:SVC isServiceInstalled - returning true AUS:SVC shouldUseService - returning true AUS:SVC getCanStageUpdates - able to stage updates using the service