Folders getting broken at random every few minutes

[Evan12345]

Hey all,

I think I've got a good one...

(Thunderbird 45.1.1 on Windows 10)

I'm having this weird problem where every time I get new mail with POP, the process is interrupted over and over again by a message that says:

The messages could not be filtered to folder 'Example' because adding a message to it failed. Verify that the folder is displaying properly or try to repair it from the folder properties.

The result is that every time I download new mail, I have to click "OK" a bunch of times, and afterwards any messages which my custom filters should have moved to the folders named in the error dialogue have not been moved, and are still sitting in the inbox ("Tools > Run filters on folder" works as a manual way to correct the latter problem after the fact). If I click on one of the folders in question, it indeed does not display correctly, though once I'm there it either fixes itself automatically or resolves after hitting "Repair" in the properties (I can even do this during the downloading of new messages, and if it's repaired before more messages get filtered to it, they are moved correctly without any error).

However, the repair is only temporary, as the same thing happens again the next time I get mail, even if only a few minutes later. It's not always the same folder - it's usually one or two of my five or so folders which receive messages moved automatically using filters. As far as I can tell, which folder(s) it happens to is selected at random each time, with the exception that it seems to happen more frequently to some folders than others (no pattern identified so far).

I imagine what's happening is that something is corrupting .msf files frequently and at random. But why??

Other things that happen: Folders that aren't getting messages filtered into them also sometimes fail to display properly when I first click on them (and occasionally take a long time to get fixed). And I occasionally get a message that says "Unable to load address book file history.mab".

I'm currently using Thunderbird 45.1.1, but this problem has persisted over several months under at least one previous version. I *suspect* that it may have started after I set up MEGAsync to automatically back up the folder containing my Thunderbird profile. I once caught it apparently downloading something into the local folder, and stopped it from syncing then. But the problem has persisted ever since. I have tried upgrading Thunderbird, running Thunderbird in safe mode, uninstalling and reinstalling Thunderbird, and going in and deleting almost all the .msf files all at once.

Needless to say, this is a pretty aggravating. Anyone have any ideas?

Really appreciate it!

-Evan

[tanstaafl]

The "repair folder" button only rebuilds the *.msf file (basically a cache of the folder listing), it does nothing for the actual mail folder. I suggest you try replacing that folder since you've already tested while running Thunderbird in safe mode.

Did you try disabling MegaSync? Several of your problems sound like it might be due to it running in the background and locking a file that its syncing. Your anti-virus scanner is another possibility, though less likely.

[Evan12345]

Thanks! I'll try those things next time I have a batch of mail to download.

The reason I've linked it to the .msf files is that repairing the folder does temporarily prevent the error dialogues from coming up. But I guess maybe it could be a problem with the folders themselves that's translating into the .msf file getting corrupted?

[tanstaafl]

Yes.

[Evan12345]

Okay, so I tried completely disabling MEGAsync for a few days, but it didn't help. And then I also tried creating entirely new folders and redirecting the filtered messages to those, but it didn't help either. The same thing started happening with the new folders right away.

Any other ideas?

[Evan12345]

"Spell check as you type" also has been malfunctioning, marking every single word as misspelled even when I make sure it's set to the right language. It's as if the dictionary file isn't being read properly or something.

[tanstaafl]

Then uninstall Thunderbird, download the setup program and re-install. Uninstalling doesn't delete your profile, which has your mail, settings, address books etc.

[Evan12345]

I already tried that. I can only assume that the problem is connected to something within my profile directory that's messed up.

[tanstaafl]

Have you had windows scan your hard disk for errors?

[sebrame]

I've been having this exact issue for months. Repairing each folder when I get the error message only seems to help for a while, then it returns.

[DanRaisch]

Have you had windows scan your hard disk for errors?

For that matter you might want to test the system RAM as well, to be sure that what is being moved from memory/cache to the hard drive is not an issue.

Also, are you closing Thunderbird each time before shutting down or rebooting the computer?

[Evan12345]

Have you had windows scan your hard disk for errors?

Good idea. Tried it, but still no luck.

Problem is happening much more often with some folders than others. Problem with spell check seems to have spontaneously resolved.

[Evan12345]

I've been having this exact issue for months. Repairing each folder when I get the error message only seems to help for a while, then it returns.

Well, kind of good to know I'm not the only one! If you solve it, please post here (I'll do the same).

[Evan12345]

For that matter you might want to test the system RAM as well, to be sure that what is being moved from memory/cache to the hard drive is not an issue.

Tried Windows memory diagnostic tool. Came up clean. Is there some other test I should be running?

Also, are you closing Thunderbird each time before shutting down or rebooting the computer?

I don't know if I always do - I don't reboot very often. But I usually do close it first, and I definitely did the last time, just now (but still having the problem).

[Linus Van Pelt]

I'm bumping this because I haven't seen a resolution suggested anywhere.

I'm having the exact same problem running Thunderbird 45.2.0 on an iMac running OS X El Capitan. I also noticed that I am needing to re-download images associated with emails in the broken folders. Running folder repair only works on a give folder for a day or two and sometimes only until I relaunch Thunderbird. The folders randomly break down. It appears to affect almost every folder I have at some point.

I did not have this problem until about two weeks ago and have tried deleting the .msf files, as well as trying to build new folders--no success in eliminating the problem. I tried running various disk diagnostics and repaired permissions as well. No success. I've been running Thunderbird without problem for about five years or so.

Thanks for any help!