Firefox is stopping my PC from operation...started downloding and got interrupted...DUH ~

Hi! I’m sorry you’re having such a frustrating experience. Firefox updates can sometimes appear to get stuck, but Firefox Sync itself should not prevent you from accessing your computer or require you to restart it. One important point is that Windows 7 is no longer supported by current Firefox releases. If Firefox started an update and then stopped, the update may not have completed successfully. If you can still open Firefox after restarting, please check ☰ → Help → About Firefox and tell us the Firefox version shown there. Also, let us know exactly what happens when Firefox becomes inaccessible (for example, does it freeze, fail to open, or show an error message?). Please don't repeatedly force the computer to shut down if you can avoid it, as that can potentially cause data loss. If the problem continues after restarting, we can troubleshoot the Firefox installation without changing your personal bookmarks or other profile data.