We're sorry to hear that your Firefox seems to be crashing when you open it. Please perform the following steps to give us a crash report ID that helps us find out more about the cause of the crash.

1. Press the following shortcut to get a Run window: [Windows] + [R]. This should bring up a window that contains a text field.
2. In that text field, enter %APPDATA% and press Enter. An explorer window should open.
3. From that explorer window, double-click on the Mozilla folder, then double-click on Firefox and then on Crash reports. Double-click on submitted.
4. Now, you should see a list of files that contain reports. Go to View > Arrange Icons by > Modified to get the most recent files at the top of the window.
5. Open the most recent 5 files with a text editor and copy the IDs.
6. 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-0ff527fb-4fad-4b11-af8a-222732140902 bp-4769d704-31af-401a-9c89-a79b02140902 bp-00e8096d-84e5-419e-9e51-f485c2140902 bp-d0e971bc-d7cb-4ee3-8e0d-98c532140902 bp-ade62a88-565f-4a30-a065-6dd402140902

Thank you. This particular kind of issue should be resolvable trough a "clean reinstall", which means you manually remove Firefox program files and then reinstall Firefox. Please follow these steps:

1. Download the latest Desktop version of Firefox from http://www.mozilla.org and save the setup file to your computer.
2. Delete the Firefox installation folder, which is located in one of these locations, by default:
   • C:\Program Files\Mozilla Firefox
   • C:\Program Files (x86)\Mozilla Firefox
3. Execute the setup file you've downloaded earlier.