Running 128.8.0esr on Win 11. I have just created a new email account in my mailserver for a colleague and have also created it in my Thunderbird. I can see it on the server and in TB and everything seems OK - except that when trying to copy emails from my own account to the new one, I had success in copying over half of one folder (about 400 messages) and then TB refused to transfer any more, either to that new folder or to another in the new account. I shut down and restarted (more than once) and it's very weird. Sometimes it will let me copy one email over, at other times it won't copy anything, but will let me move a few emails to the new account inbox (from where I can move them into the correct folder) and then copy them back into the original folder. This is obviously not feasible when I need to share several hundred more messages into the new account! I often shift messages around TB from one personal email account to another and have never had this problem. One oddity is that the new email account has placed itself right at the bottom of the left-hand pane, below Local Folders and the newsgroup account. This doesn't seem right but I can't move it to be next to the earlier email accounts. Can anyone suggest what's going wrong? Or a work around? I need to share a lot of emails with my colleague while keeping them in my own folders too. Kate (formerly known as ElviraKate but Mozilla seems to have lost me)