Join the AMA (Ask Me Anything) with the Firefox leadership team to celebrate Firefox 20th anniversary and discuss Firefox’s future on Mozilla Connect. Mark your calendar on Thursday, November 14, 18:00 - 20:00 UTC!

This site will have limited functionality while we undergo maintenance to improve your experience. If an article doesn't solve your issue and you want to ask a question, we have our support community waiting to help you at @FirefoxSupport on Twitter and/r/firefox on Reddit.

Avatar for Username

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

This thread was archived. Please ask a new question if you need help.

This address isn't valid

  • 1 reply
  • 33 have this problem
  • 13 views
  • Last reply by cor-el

bridgeld
bridgeld
more options

when I click on the Firefox icon the Firefox page won't load. I get the error message that says "The address isn't valid" Undernieth It says The URL is not valid and can't be loaded. I don't know why the browser won't open it had worked up until yesturday.

when I click on the Firefox icon the Firefox page won't load. I get the error message that says "The address isn't valid" Undernieth It says The URL is not valid and can't be loaded. I don't know why the browser won't open it had worked up until yesturday.

All Replies (1)

cor-el
cor-el
  • Moderator
  • Top 10 Contributor
more options

Start Firefox in Safe Mode to check if one of the extensions (Firefox/Tools > Add-ons > Extensions) or if hardware acceleration is causing the problem (switch to the DEFAULT theme: Firefox/Tools > Add-ons > Appearance).

  • Do NOT click the Reset button on the Safe Mode start window or otherwise make changes.

You can use one of these to start Firefox in Safe Mode:

  • On Windows, hold down the Shift key while starting Firefox with a double-click on the Firefox desktop shortcut
  • On Mac, hold down the Options key while starting Firefox
  • Help > Restart with Add-ons Disabled

You can check for problems with preferences and rename or delete the prefs.js file and possible numbered prefs-##.js files and a possible user.js file to reset all prefs to the default value.