This happens when there is a problem with the unnumbered prefs.js file. Firefox always creates a numbered temp file and when that has finished properly then this file is renamed to prefs.js to replace the current version of this file. It is likely that some security software is blocking this file against changes if the numbered file stays.

You will have to delete all pref-##.js and prefs.js files to see if that prevents numbered file from showing up.

• http://kb.mozillazine.org/Multiple_profile_files_created

Thank you Cor-el for your speedy response. Your explanation sure sounds plausible. I am not sure why it is only a couple of my profiles that this is happening. I have about 6 profiles for different purposes and the rest do not have this problem. I am going to check to see what these affected profiles have in common. Right off hand I know they have add-ons for watching and downloading videos. That would probably be a good place to look. Thank you

Here's an update. I think I found the problem I checked the properties of the "Prefs.js" file that has data and noticed that it was set to read-only, not allowing new data to be written. I unticked the read-only box and ran that profile and Voila! it works. So far no multitudes of Prefs.js files in the folder. It would be interesting to find out how it became read-only. Possibly an add-on or extension caused it. The saga continues...