Where did you install Firefox from? Help Mozilla uncover 3rd party websites that offer problematic Firefox installation by taking part in our campaign. There will be swag, and you'll be featured in our blog if you manage to report at least 10 valid reports!

Search Support

Avoid support scams. We will never ask you to call or text a phone number or share personal information. Please report suspicious activity using the “Report Abuse” option.

Learn More

Cannot open the settings window.

more options

When I try to open the settings window the result is: Invalid address. So I cannot make any changes to settings.

When I try to open the settings window the result is: Invalid address. So I cannot make any changes to settings.

All Replies (1)

more options

Have you tried to reinstall Firefox? Or if that doesn't work, go to about:support and then click Refresh Firefox... on the right?