This happens on a specific IMAP server, I can't reproduce it on my IMAP GMAIL account for example. Here's the procedure to reproduce it: 1. Create a folder in INBOX/Travel/Misc 2. Put an email in that folder 3. Move the folder 'Misc' in INBOX/ 4. 'Misc' still contains the email 5. Move back 'test' folder in INBOX/Travels/ 6. 'Misc' folder is now empty :-/ I attached the logs corresponding to step 5. From the logs one case see: ** IMAP error on gwmail.xxx.com: protocol error(very probably non-RFC compliance from the server) ** IMAP4 connection broken which suggests that there's something wrong on the server side or something not supported. If it's really the case, I think Claws should do the necessary for trying to make it works in order to support such (broken) servers. Or at least reports the error to the user and do *nothing*. But in any cases, it should LOST emails SILENTLY. BTW Thunderbird chooses to work perfectly fine here. This affects Claws 3.11 as well. I already reported it on Claws' mailing list but it didn't get any attention althouth it's a critical bug IMHO specially when emails are lost !
Created attachment 1569 [details] Network log
Here's the log from "claws-mail --debug" when doing the following step: 1. a folder INBOX/lists/test contains 1 email 2. Move the folder 'test' in INBOX/ 3. INBOX/test folder still contains the email 4. Move back 'test' folder in INBOX/lists/ 5. INBOX/lists/test folder is now empty :-/ HTH
Created attachment 1573 [details] claws-mail --debug