User Agent: Mozilla/5.0 (Windows NT 5.1; rv:32.0) Gecko/20100101 Firefox/32.0 Build ID: 20140911151253 Steps to reproduce: Retrieve new emails from my hotmail account using pop3 with the setting set to leave the messages on the server. Read emails and delete those that do not need to be saved. Actual results: Randomly (read not every time but regularly) deleted emails reappear sometimes only once, sometimes they reappear multiple times. This issue has been happening for a couple of weeks now and only on my hotmail account. The gmail and yahoo accounts work perfectly fine. Expected results: What happened before and should still be happening now is that the emails should stay deleted and not get downloaded again.