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thunderbird installation fail

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thunderbird stopped working after years. but it is not letting me do a clean install. i ran Revo Uninstaller to make sure i cleaned out previous bits of the program. used CCleaner to make sure every other fragment was removed, and restarted my windows 11 pro pc. then downloaded a fresh copy of thunderbird, and installed. everything worked well, got to the "FINISH" button, and it asked if i wanted to start thunderbird.

then i get this error message: "Thunderbird is already running, but is not responding. The old Thunderbird process must be closed to open a new window."

how is this even possible? i made sure every vestige of thunderbird had been removed!

thunderbird stopped working after years. but it is not letting me do a clean install. i ran Revo Uninstaller to make sure i cleaned out previous bits of the program. used CCleaner to make sure every other fragment was removed, and restarted my windows 11 pro pc. then downloaded a fresh copy of thunderbird, and installed. everything worked well, got to the "FINISH" button, and it asked if i wanted to start thunderbird. then i get this error message: "Thunderbird is already running, but is not responding. The old Thunderbird process must be closed to open a new window." how is this even possible? i made sure every vestige of thunderbird had been removed!

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just to be thorough, i did it all again, but this time i opened task manager and made sure there were no processes running for thunderbird BEFORE i did a clean install. i got the same error message opening up thunderbird: Thunderbird is already running, but is not responding. The old Thunderbird process must be closed to open a new window.

what gives.

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by luck i stumbled upon the solution. I went into USERS/myname/apps, also the roaming one, and deleted any folders that said THUNDERBIRD or MOZILLA on them. then i clicked on the tunderbird icon, and it opened right up. and surprisingly, all my stored emails were still there!