Hello, I have started using Thunderbird these past few weeks as part of a move away from Gmail. I made some folders and setup some message filters to automatically sort my emails into those folders, to replicate my tags in Gmail. When I was doing this, one folder failed to create initially (let's call it "myFolder"). It simply wouldn't appear after trying to create it, even on repeated attempts, although I could still create other folders fine with a different name (so presumably myFolder was partially created somewhere in the backend and couldn't be overwritten). Anyway, I managed to solve this eventually, although I forget how. Maybe just refreshing the connection or restarting the program. Anyway, this morning I updated to 115.7.0 (32-bit), and on applying the update I managed to briefly catch a message when the program restarted saying "Deleting myFolder". And sure enough, that folder has been deleted along with all of its email contents (which is rather a lot of emails!). There is nothing in the Archives nor Deleted folders. All of my other folders are still intact just fine. If I go to my \ImapMail\[server]\INBOX.sbd folder, I can see all the other folders there, but not the deleted myFolder one. And same story if I look in the folderCache.json or folderTree.json files. I can also access the account in question via RoundCube and SquirrelMail web interface. In the former it shows all the other IMAP folders I created in Thunderbird, but not the one deleted on update. In the latter it shows the first folder I created in Thunderbird, but none of the rest (I think myFolder was the second or third I created). I cannot see any kind of backup profile. I only appear to have an empty .default profile, and the active .default-release profile. There is also nothing new in my Windows Recycle Bin. 1. Can someone please help firstly with recovering the lost folder? Or at least all my emails that were in it? 2. As a second priority I would obviously be interested to learn what caused this, and how to avoid any risk of it happening again in the future? I am amazed that Thunderbird would automatically and permanently delete large numbers of emails in one go both locally and off the server, without any user interaction/confirmation, and without any way to undo it? Might it be safer to just use local Tags in Thunderbird rather than synced IMAP folders? I wasn't sure how to manage those automatically with filters, but now I have found a suggestion advising that it can be done with Saved Searches. If I create a new Saved Search Folder, I presume that would then just be a local view folder which I could filter by tags into, and wouldn't have any impact on the server? Best wishes, Brian