Firefox will not allow any new windows to open when clicking on a link which opens a new window
When clicking on any link which opens a new window, Firefox will do nothing when I click on the link. Then, if I close Firefox, I cannot open it again as it says something along the lines of "Firefox is already running on this computer."
I read that this may be a Java issue, but I have installed the latest version of Java AND the latest version of Firefox.
This issue occurs on any website in which a link opens a new window (for example, when on ebay, clicking the "enlarge" button beneath the photo on a listing).
Alla svar (1)
Start Firefox in Diagnose Firefox issues using Troubleshoot Mode to check if one of your add-ons is causing your problem (switch to the DEFAULT theme: Tools > Add-ons > Themes).
See Troubleshoot extensions, themes and hardware acceleration issues to solve common Firefox problems and Troubleshoot issues with plugins like Flash or Java to fix common Firefox problems
See also http://kb.mozillazine.org/Firefox_hangs and Firefox hangs or is not responding - How to fix (Hang at exit)