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400 Bad Request HTTPS over Vital Security Proxy FF 10.0.1, 1o.0.2

  • 3 replies
  • 1 has this problem
  • 1 view
  • Last reply by ftibi

ftibi
ftibi
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I use Firefox on W7 in the office. Our company uses a Proxy from Vital Security for Internet access. After upgrading from FF 9.0.1 to FF 10 (including 10.0.2), I have problems accessing HTTPS sites. The proxy returns the following error message: 

   HTTP Error Status: 400 Bad Request
   Error Reason: Malformed HTTP request

It still works without any problems from IE or after downgrading to FF 9, so it's definitely a FF 10 issue.

I use Firefox on W7 in the office. Our company uses a Proxy from Vital Security for Internet access. After upgrading from FF 9.0.1 to FF 10 (including 10.0.2), I have problems accessing HTTPS sites. The proxy returns the following error message: HTTP Error Status: 400 Bad Request Error Reason: Malformed HTTP request It still works without any problems from IE or after downgrading to FF 9, so it's definitely a FF 10 issue.

Modified by ftibi

Chosen solution

Update: the problem disappeared without me changing anything (FF 10.0.2). Most likely there was a problem on the proxy itself rejecting valid requests for some reason, maybe having problem with the user agent in the filtering rules. So it was not a Firefox problem. Thanks for your support.

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All Replies (3)

cor-el
cor-el
  • Moderator
  • Top 10 Contributor
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That issue can be caused by corrupted cookies.

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

"Clear the Cache":

  • Tools > Options > Advanced > Network > Offline Storage (Cache): "Clear Now"

"Remove Cookies" from sites causing problems:

  • Tools > Options > Privacy > Cookies: "Show Cookies"
ftibi
ftibi Question owner
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Hi cor-el

I tried the indicated steps (cleaned cache and cookies completely), unfortunately it still doesn't work. I cannot imagine what causes the issue - it works without proxy and it only gets the bad HTTP request on certain HTTPS requests. If you have more ideas, pls. let me know - I am happy to try them out.

ftibi
ftibi Question owner
more options

Chosen Solution

Update: the problem disappeared without me changing anything (FF 10.0.2). Most likely there was a problem on the proxy itself rejecting valid requests for some reason, maybe having problem with the user agent in the filtering rules. So it was not a Firefox problem. Thanks for your support.

Modified by ftibi