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The other day, all of my firefox websites started to load incorrectly.

  • 2 replies
  • 9 have this problem
  • 5 views
  • Last reply by Morbus

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Last Thursday, all of a sudden out of nowhere, facebook, gmail, and EBSCO (a research database) and several other websites stopped loading correctly. I get a message from gmail saying that my browser is not supported, but it's the same one I've been using. Facebook chat doesn't work and the other websites, including my bank, won't load. I click on "next" buttons and it just refreshes the page but won't navigate to other pages. The whole thing is just acting really buggy but I didn't install any updates or anything, so I don't get it! I tried deleting it and reinstalling it, but that didn't work. I'm using a macbook w/ OS X. Please let me know if you can help! Thank you very much.

This happened

Every time Firefox opened

I was on facebook chatting with friends.

User Agent

undefined GoogleToolbarBB

Last Thursday, all of a sudden out of nowhere, facebook, gmail, and EBSCO (a research database) and several other websites stopped loading correctly. I get a message from gmail saying that my browser is not supported, but it's the same one I've been using. Facebook chat doesn't work and the other websites, including my bank, won't load. I click on "next" buttons and it just refreshes the page but won't navigate to other pages. The whole thing is just acting really buggy but I didn't install any updates or anything, so I don't get it! I tried deleting it and reinstalling it, but that didn't work. I'm using a macbook w/ OS X. Please let me know if you can help! Thank you very much. == This happened == Every time Firefox opened == I was on facebook chatting with friends. == == User Agent == undefined GoogleToolbarBB

All Replies (2)

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Hello Libby.

See this support article:

http://support.mozilla.com/en-US/kb/Websites+look+wrong

I hope it helps. If it doesn't, you may be having a problem with some Firefox add-on that is hindering your Firefox's normal behavior. Have you tried disabling all add-ons (just to check), to see if Firefox goes back to normal?

Whenever you have a problem with Firefox, whatever it is, you should make sure it's not coming from one of your installed add-ons, be it an extension, a theme or a plugin. To do that easily and cleanly, run Firefox in safe mode and select Disable all add-ons. If the problem disappears, you know it's from an add-on. Disable them all in normal mode, and enable them one at a time until you find the source of the problem. See this article for information about troubleshooting extensions and theme. You can troubleshoot plugins the same way.

If you want support for one of your add-ons, you'll need to contact its author.

Also, make sure you are running a supported version of Firefox. Firefox 3.5.9 or 3.6.3 are the versions supported at present. Previous versions have been discontinued and are no longer supported. Furthermore, they have known bugs and security problems. I urge you to update to the latest version of Firefox, for maximum stability, performance, security and usability. You can get it for free, as always, at getfirefox.com.

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Check the general.useragent prefs on the about:config page. You can open the about:config page via the location bar, just like you open a website. Filter: general.useragent If any general.useragent prefs are bold (user set) then right-click that pref and choose Reset.

See Find what version of Firefox you are using and Web sites or add-ons incorrectly report incompatible browser See also http://kb.mozillazine.org/Resetting_your_useragent_string_to_its_compiled-in_default