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Bad REquest

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I have never had a problem opening my email client before in Firefox, but now after the last time I started my computer I get this message when I try to open my email client (Shaw Webmail):

400 Bad Request Request Header Or Cookie Too Large nginx/1.24.0

Oddly though, it will open if I go into the Incognito window. Why is this happening and how can I fix it so I don't have to constantly into Incognito mode to access it?

I have never had a problem opening my email client before in Firefox, but now after the last time I started my computer I get this message when I try to open my email client (Shaw Webmail): 400 Bad Request Request Header Or Cookie Too Large nginx/1.24.0 Oddly though, it will open if I go into the Incognito window. Why is this happening and how can I fix it so I don't have to constantly into Incognito mode to access it?

Alle Antworten (4)

Thank you jonzn4SUSE, I tried it. But it didn't work.

A 400 "Bad Request" error issue is usually caused by corrupted cookies.

Clear the Cache and remove the Cookies for websites that cause problems via the "3-bar" Firefox menu button (Settings), click the padlock icon (Clear cookies and site data) for the domain in the selected tab.

"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 if userChrome.css/userContent.css is causing the problem.

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

Same problem did all the suggested and still 400 error persists.