Hi kena435,

I'd try starting Firefox in Diagnose Firefox issues using Troubleshoot Mode. If you don't have the issue while all of your add-ons, extensions, and themes are disabled, you can try adding them back in one by one until you find the culprit. You should look at the Extensions and Themes troubleshooting guide and the Troubleshoot issues with plugins like Flash or Java to fix common Firefox problems article as well.

You could also try Creating a new profile.

Hopefully this helps!

thank you so much, I tried but I can not even open a window , is there another way to open on safe mode? so sorry, I am not an expert in computers and computer language

See also:

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

You can hold down the Shift key while starting Firefox 11 (4+ versions) to start Firefox in Safe mode and get the window with the safe mode options to select.

• https://support.mozilla.org/kb/Safe+Mode
• http://kb.mozillazine.org/Safe_Mode