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Error message browser sent invalid command

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  • 1 has this problem
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  • Last reply by cor-el

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After clicking on a link,, the following error message appears. It happens with various links and follows an automatic upgrade to FF 18.0.

400 Bad request Your browser sent an invalid request.

After clicking on a link,, the following error message appears. It happens with various links and follows an automatic upgrade to FF 18.0. 400 Bad request Your browser sent an invalid request.

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This error can be caused by corrupted cookies.

Clear the cache and the cookies from sites that cause problems.

"Clear the Cache":

  • Tools > Options > Advanced > Network > Cached Web Content: "Clear Now"

"Remove Cookies" from sites causing problems:

  • Tools > Options > Privacy > Cookies: "Show Cookies"