Uninstalling the program doesn't affect your data in the profile folder. If TB 64-bit is installed in Program Files, and TB 32-bit is installed in Program Files (x86), go ahead and uninstall the 32-bit version.

Hi, Thanks for the advice

Thunderbird 32-bit appears to be installed in C:\Program Files\Mozilla Thunderbird and Thunderbird 64-bit appears to be installed in C:\Program Files (x86)\Mozilla Thunderbird

Unfortunately when I uninstall the 32-bit version all the account settings (and I'm not sure what else disappear when I start the 64-bit version of Thunderbird). Luckily I had a system restore point to go back to.

Any other suggestions?

Thanks, Dave

I don't know why the program was installed in the wrong directories, but your data in the profile folder should still be there. The problem is to get TB to read the correct profile. Try this: Windowskey+R and type

thunderbird.exe -p

to show the list of profiles, then select the default and see if it loads your data.

Hi,

Thanks for that suggestion. I get the message "Your Thunderbird profile cannot be loaded. It may be missing or inaccessible." when I select the default option.

Cheers, Dave

Yikes!

Now I can't start Thunderbird

Yikes!

Now I can't start Thunderbird. I get the message "Your Thunderbird profile cannot be loaded. It may be missing or inaccessible."

I've rebooted the PC and no change

Cheers, Dave

I think you should use the restore point and go back to where TB 64-bit is working. Leave the 32-bit version alone, it's not doing any harm. Trying to explain how to untangle this mess in a forum is not productive. It's not your fault that the TB developers decided to adopt an unwieldy system of versions and profile policies that have caused innumerable headaches.

OK - will reverting to yesterdays system restore point restore my email folders to yesterdays state - namely loosing all emails received today?

If your accounts are IMAP, all past and current mail will be downloaded. If they are POP, and messages are deleted from the server after being downloaded, today's messages are stored in whatever profile folder was being used today. In that case, backup your profile folder before restoring to an earlier state so that eventually today's mail can be recovered.

https://support.mozilla.org/en-US/kb/profiles-where-thunderbird-stores-user-data#w_backing-up-a-profile

Thanks, All back to square 1 again with email working.