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I keep getting 400 Bad Request

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  • 0 have this problem
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  • Last reply by cor-el

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I have Windows 10 and use Firefox, but I keep getting "400 Bad Requests "....I am old and can't seem to Clear the problem from my computer.

Could you possible send me a detailed procedure to clean my browser cache, browser cookies and speeds up my computer ?

[removed email from public]

I have Windows 10 and use Firefox, but I keep getting "400 Bad Requests "....I am old and can't seem to Clear the problem from my computer. Could you possible send me a detailed procedure to clean my browser cache, browser cookies and speeds up my computer ? [removed email from public]

Modified by James

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A Bad Request is usually caused by a problem with corrupted cookies.

You can clear the Cache and remove the Cookies for websites that cause problems via the "3-bar" Firefox menu button (Settings) or for the website in the current tab via the padlock icon.

"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

If clearing cookies doesn't help, it is possible that the cookies.sqlite file in the Firefox profile folder that stores the cookies got corrupted.

  • rename/remove cookies.sqlite (cookies.sqlite.old) and when present delete cookies.sqlite-shm and cookies.sqlite-wal in the Firefox profile folder with Firefox closed in case cookies.sqlite got corrupted.

You can use the button on the "Help -> More Troubleshooting Information" (about:support) page to go to the current Firefox profile folder or use the about:profiles page (Root directory).