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Opening Browser and Opening/singing in on new tabs

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I have tried to get help regarding the 2 problems that I feel are related. I use Norton as my security system, they say that Firefox is up to day. When I try to start Firefox it takes two or three times clicking on the icon before it stays open. Then when I need to open a new tab to go to a website that I have opened a hundred times, sometimes it will not even open the website and other times it will open but not let me sign in. On the sign in page to error this morning said: Bad Request - "Your browser sent a request that this server could not understand. Size of request header field exceeds server limit."

It will often just say it can't start that page, try again.

The "try again" has been going on for awhile, the Bad Request is new. Please help me with this problem! It is beginning to get annoying.

Thanks for your help. [email and phone# removed from public view]

HJ Feagins

I have tried to get help regarding the 2 problems that I feel are related. I use Norton as my security system, they say that Firefox is up to day. When I try to start Firefox it takes two or three times clicking on the icon before it stays open. Then when I need to open a new tab to go to a website that I have opened a hundred times, sometimes it will not even open the website and other times it will open but not let me sign in. On the sign in page to error this morning said: Bad Request - "Your browser sent a request that this server could not understand. Size of request header field exceeds server limit." It will often just say it can't start that page, try again. The "try again" has been going on for awhile, the Bad Request is new. Please help me with this problem! It is beginning to get annoying. Thanks for your help. [email and phone# removed from public view] HJ Feagins

James trɔe

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A "Bad Request" issue is usually caused by corrupted cookies and you can fix this by removing the cookies for this website.

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

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)

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