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.

Cannot log into Facebook

  • 3 replies
  • 1 has this problem
  • 1 view
  • Last reply by cor-el

philipp.leite
philipp.leite
more options

See above. I'm able to log into it on other browsers, but on Firefox I only get a "Login Error. An unexpected error occurred. Please try logging in again."

See above. I'm able to log into it on other browsers, but on Firefox I only get a "Login Error. An unexpected error occurred. Please try logging in again."

All Replies (3)

Zmingong
Zmingong
more options

Hi philipp.leite,

A third-party plugin may be causing problems for Firefox when working with Facebook. You can try to disable some of the add-ons (if you have any) or you can try to clear cookies and site data by going [Settings -> Privacy & Security -> Cookies and Site Data -> Clear Data] and restart the browser to see if it help.

Another option you can try Firefox Safe Mode to troubleshoot: https://support.mozilla.org/en-US/kb/diagnose-firefox-issues-using-troubleshoot-mode https://support.mozilla.org/en-US/kb/troubleshoot-extensions-themes-to-fix-problems

Hope it helps you!

philipp.leite
philipp.leite Question owner
more options

This seems to be a very general response. I've tried this, and various other things, including un-and-re-installing the application, logging in through private windows, on another machine, etc. No luck.

Modified by philipp.leite

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

This issue can be caused by corrupted cookies or blocked cookies.

  • check the permissions for the domain in the currently selected tab in "Tools -> Page Info -> Permissions"

You can try these steps in case of issues with webpages:

You can reload webpage(s) and bypass the cache to refresh possibly outdated or corrupted files.

  • hold down the Shift key and left-click the Reload button
  • press "Ctrl + F5" or press "Ctrl + Shift + R" (Windows,Linux)
  • press "Command + Shift + R" (Mac)

clear the Cache and remove the Cookies for websites that cause problems via the "3-bar" Firefox menu button (Settings).

"Remove the Cookies" for websites that cause problems:

  • Settings -> Privacy & Security
    Cookies and Site Data: "Manage Data"

"Clear the Cache":

  • Settings -> Privacy & Security
    Cookies and Site Data -> Clear Data -> [X] Cached Web Content -> Clear

Start Firefox in Troubleshoot Mode to check if one of the extensions ("3-bar" menu button or Tools -> Add-ons -> Extensions) or if hardware acceleration or userChrome.css is causing the problem.

  • switch to the DEFAULT theme: "3-bar" menu button or Tools -> Add-ons -> Themes
  • do NOT click the "Refresh Firefox" button on the Troubleshoot Mode start window