Inbox repeatedly corrupts
I'm using Thunderbird 52.x, but this issue goes back several major versions. I'm using it on two computers, both Win10, but the problem predates these computers to my old one with Win7.
The Inbox, at the very least, constantly corrupts. This happens when I am deleting messages. I will be deleting a message and in the message list, a DIFFERENT message goes away. If I close and reopen the program, the correct message is gone and the one that was missing is back. It happens on both installs, though more often on the laptop than the desktop.
Sometimes, it completely corrupts and I'll get an unread empty subject line with a date in 1969, that can not be opened, marked read or deleted without doing a database repair.
I do not recall it happening when moving messages (drag and drop) to other folders.
Both computers have 1TB drives with hundreds of gigabytes free, and 8GB of RAM. Both run Win10 Home.
Account is IMAP. If I use another mail client on the same account, this never, ever, happens.
Alla svar (6)
It sounds like your mail files are corrupted. First of all create a backup of your Thunderbird profile folder. https://support.mozilla.org/kb/profiles-tb#w_backing-up-a-profile
Then try to rebuild the index file of the troubled folder. Right-click the folder - Properties - Repair Folder
Note: depending on the corruption this may erase messages from the affected folder which cannot be recovered anymore. In that case you'd need to restore them from a recent backup done prior to the corruption.
Corruption is often caused by anti-virus software messing with Thunderbird mail files. It is therefore recommended to create an exception for the Thunderbird profile folder, so that the real-time scanner won't attempt to scan the profile with your mail.
For more information on the profile location see http://kb.mozillazine.org/Profile_folder_-_Thunderbird
Also see http://kb.mozillazine.org/Keep_it_working_-_Thunderbird
I've actually done all that. I've even completely wiped TBird from both computers, including the profile folders to get rid of the message files, and reinstalled from scratch.
Do you allow Thunderbird to compact regularly? Do you allow large numbers of messages to accumulate in Inbox?
Ideally neither of these behaviours would be problematic, but in practice many users with a large Inbox, or who choose not to allow compacting do suffer from corruption. It does seem to be a weakness of Thunderbird's mail store system.
My own Inbox and Sent folders are kept empty. Messages are promptly filed or deleted and not allowed to linger there. Thunderbird is set to auto-compact at quite modest levels of data storage recovery.
Zenos said
Do you allow Thunderbird to compact regularly? Do you allow large numbers of messages to accumulate in Inbox?
Yes and no, in that order. TBird is set to compact when it will save at least 2MB of space, and I consider the Inbox to be a temporary storage location, I either move or delete messages when I no longer need them there. I currently have 11 messages in my Inbox, it has gone as high as 30.
Ideally neither of these behaviours would be problematic, but in practice many users with a large Inbox, or who choose not to allow compacting do suffer from corruption. It does seem to be a weakness of Thunderbird's mail store system. My own Inbox and Sent folders are kept empty. Messages are promptly filed or deleted and not allowed to linger there. Thunderbird is set to auto-compact at quite modest levels of data storage recovery.
Not sure how the device folder structure interacts with the mailbox folder structure, but all of my mail subfolders are shown as subfolders of the Inbox. In Windows, they are subfolders.
What anti virus are you using? They have a habit od scanning the "changed" file and Thunderbird then generates a corrupt index for some reason to do with file contention. Historically anti virus did not scan Thunderbird mbox files as the are text files. but this behavior appears to have changed in recent years. I suggest a scanning exception for scanning for the mail and IMAP mail folders in your profile and see if that helps.
Matt said
What anti virus are you using? They have a habit od scanning the "changed" file and Thunderbird then generates a corrupt index for some reason to do with file contention. Historically anti virus did not scan Thunderbird mbox files as the are text files. but this behavior appears to have changed in recent years. I suggest a scanning exception for scanning for the mail and IMAP mail folders in your profile and see if that helps.
I was using Avast. I have since removed it and am just using Windows Defender. No change. Until today, I had not set any scanning exceptions in Defender, but I think I had the TBird profile folder excluded in Avast, but I honestly cannot say for sure.
Today, after reading the first response to my question, I did set the exclusion in Defender for the ImapMail folder, on both computers.