User-Agent: Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.8) Gecko/20051111 Firefox/1.5 Build Identifier: Thunderbird version 1.5 (20051201) This happens with thunderbird and with firefox. If the name of the profile directory in the profiles.ini does not match with the name of the profile directory you get an error message saying "Thunderbird is already running, but is not responding. To open a new window, you must first close the existing Thunderbird process, or restart your system." There were no firefox nor thunderbird running, i just renamend the directories and had a typo in the profiles.ini. Reproducible: Always Steps to Reproduce: 1. Go into your thunderbird/firefox directory and change the name of the profile directory (or the entry in the profiles.ini) 2.start firefox/thunderbird with this profile. Actual Results: You get the error message mentioned above. Expected Results: An error message telling me that "Profile directory <dir-name-in-profiles-ini> does not exist and/or start the profile manager.

Confirmed with Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.9a1) Gecko/20060126 Firefox/1.6a1 ID:2006012604

*** This bug has been marked as a duplicate of 278860 ***