User-Agent: Mozilla/5.0 (compatible; Konqueror/3.2; Linux) (KHTML, like Gecko) Build Identifier: Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.6) Gecko/20040614 Firefox/0.8 This problem happened when my laptop battery got empty and everything collapsed suddenly while browsing using firefox. after connecting the AC adapter and turning on the laptop once again, I tried opening the firefox. It first asked me (Firefox profile manager) to select a user profile. And since I only have one profile (which is the default), so I selected it and hit the "start firefox" button. Then, I get the Alert message displaying "firefox cannot use the profile default because it is in use. Please choose another profile or create a new one". neither top nor ps shows any firefox instances running. This problem happened to me before but I can't remember why did it happen. I am running Debian GNU/Linux testing. Reproducible: Always Steps to Reproduce: 1. 2. 3.

Try removing any file named 'lock' that you find anywhere in your FF profile directory.

*** This bug has been marked as a duplicate of 151188 ***