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Thunderbird 78.6.1 can not be started - former installation is not installed properly

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  • Last reply by Toad-Hall

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On a seldom used PC i cannot start thunderbird. If trying to update i get the message, that update is not possible cause a former update is not installed ready. New start and all other tried before is no solution. Deinstallation of thunderbird is also not possible with same reason.

On a seldom used PC i cannot start thunderbird. If trying to update i get the message, that update is not possible cause a former update is not installed ready. New start and all other tried before is no solution. Deinstallation of thunderbird is also not possible with same reason.
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re :Deinstallation of thunderbird is also not possible

Exit Thunderbird. Thunderbird is usually installed in: C:/ Program Files (x86)/Mozilla Thunderbird So you could just delete all the files and folders which are in the 'Mozilla Thunderbird' folder.

Try to download and install the same version 78.6.1 http://ftp.mozilla.org/pub/thunderbird/releases/78.6.1/

If using Windows 32bit then select win32 If using Windows 64bit then select win64

then choose the language Click on the 'Thunderbird Setup 78.6.1.exe ' link to get download. It may get automatically downloaded to your 'downloads' folder Click on it to run.

Make sure to install in same location.

I suggest you create a backup of the Profile before you try to upgrade to version 91.1.2 http://ftp.mozilla.org/pub/thunderbird/releases/91.1.2/

Ext Thunderbird and then access the following location. Use image below as guide. Backup is usually here: C:Users/User Account /Appdata/Roaming/Thunderbird Copy the Thunderbird folder to an external hardrive.