My Thunderbird inbox stopped accepting messages with a message 'Unable to write the email to the mailbox. Make sure the file system allows you write privileges, and you have enough disk space to copy the mailbox.' I 'repaired' the folder but all my junk messages suddenly reappeared in my inbox (a lot of them!). Tools didn;t work (wanted to re-apply junk filter). Went into safe mode - no difference. Now can't get any tools to work on the inbox folder. Not sure what to try next. Help much appreciated.