- Windows 8 Pro 32 bit - It happens with two different user accounts on the same machine, different mail accounts, one POP, one IMAP. - I have no extensions - I have only the default appearance - I have set all plugins to "Never activate" - I have uninstalled and re-installed the latest Thunderbird, as of 2nd August 2014 - I have purged as many e-mails as I can - I have compacted all folders - I have tried safe mode as advised in a number of threads - I have run for a time with no AV - I have also run "repair folder" on every folder None of the above makes a difference. Two different user accounts, different profiles, three e-mail servers one POP (on one user account), two IMAP (both on the other user account). E.g. I sent a message to myself. As soon as the message arrived I deleted it, no problem. Then I went to the sent folder and deleted the copy there and TB hung. During the time it was hung I was able to ping the mail server with no problem. Sometimes it hang when deleting from the inbox, sometimes also hangs when moving messages.