We're sorry to hear that Firefox is crashing when you open it. Please do the following to give us crash IDs that will help us understand more about the crash.

1. (OS X 10.6 or previous) Click the Finder icon in the dock. Your home folder will be selected. In the right side of the window, click the Library folder to open it. Then open the "Application Support" folder, the "Firefox" folder, the "Crash Reports" folder and finally the "submitted" folder.
   (OS X 10.7 or above) Click the Finder icon in the dock. On the menu bar, click the Go menu, hold down the option or alt key and select Library. A window will open containing your Library folder. Then open the "Application Support" folder, the "Firefox" folder, the "Crash Reports" folder and finally the "submitted" folder.
2. Open the 5 most recent files with a text editor and copy the IDs.
3. Paste each ID with bp- into the reply window on the forums.

Thanks in advance!

You can find more information and troubleshooting steps in the Troubleshoot Firefox crashes (closing or quitting unexpectedly) article.

bp-7e11ef35-1cbf-441a-8567-822480221011 bp-9e4b28bf-10fb-4f5b-b962-e01a00221011 bp-467513bd-a36c-4fc1-9e69-065db0221011 bp-08807217-62a6-4120-a30b-664290221011 bp-a82ae378-008b-47cf-bc17-8ae000221011