There should be nothing that installing a 32bit version fixes, except perhaps some MAPI errors.

If you settings will not stay set there are some tings to look out for.

ccleaner (it deletes Thunderbird settings to "protect your privacy") How many copies of prefs.js are to be found in your profile folder. https://support.mozilla.org/en-US/kb/profiles-where-thunderbird-stores-user-data

You may see multiple copies with a number inserted. I have heard of up to 99 for those with particularly bad issues with their antivirus preventing writes for settings.

There is only one prefs.js but there seem to be 47 foldercache.json

Not sure where I go from here.

To be as precise as possible, I originally had the latest TB 64-bit. Started having issues with the unified folder not displaying (would not stay checked in folder view options).

Uninstalled TB and downloaded BetterBird hoping that would help. Hated BetterBird. Did more research on unified folder problems with TB and heard downloading 32-bit might help. Worked at first but after restart it was the same problem. I had CCleaner installed recently to clean up primary OS drive but uninstalled after using.

I tried booting TB in safe mode, did not help. I don't have any add-ons or extensions anyways.

I guess I could do another uninstall/install?? I use quite a few email addresses and this is driving me crazy.

Thanks!

Is your profile in the default location ? eg: C:/Users/User name/Appdata/Roaming/Thunderbird/Profiles/<profile name>

Where did you get the Thunderbird download? eg advise you use the Official website: https://www.thunderbird.net/en-US/thunderbird/all/

First set up Thunderbird so you are only using View > Folders > All

then Clean up Thunderbird profile folders Exit Thunderbird In profile name folder delete all the following:

• all the 47 foldercache.json files
• virtualFolder.dat file
• In Mail folder delete the smart mailboxes folder.

Uninstall Thunderbird - In Windows OS - As you have downloaded both 64 and 32 in the past - Thunderbird may be installed in either or both of the following locations, so make sure it's not in either location. You could simply delete the 'Mozilla Thunderbird' folder.

• C:/Program Files/Mozilla Thunderbird
• C:/Program Files (x86)/Mozilla Thunderbird

As my profile was originally created when I used 32bit Thunderbird, when I updated to the 64bit version, I installed the 64bit into the same location usually used for 32bit. Why - Back when the 64 bit was first offered, there were some issues experienced by some people, which did not occur if installed in original location. So maybe doing the following could help in your case - perhaps you originally used 32 years ago.

I just completely emptied the 'Mozilla Thunderbird' folder which contains the program. In other words I still had: C:/Program Files (x86)/Mozilla Thunderbird But nothing in the 'Mozilla Thunderbird' folder. So after downloading the 64bit version, when installing I chose the 'custom' option, this meant I could select that 'Mozilla Thunderbird' location for the install - C:/Program Files (x86)/Mozilla Thunderbird

Start Thunderbird Allow download etc to complete for all your mail accounts. Then reselect the View > Folders > 'Unified' option.