From Bugzilla Helper: User-Agent: Mozilla/5.0 (Windows; U; Win98; en-US; m18) Gecko/20001123 BuildID: 2000112320 About 75% of the time i get proxy errors while trying to surf the web. I often have to hit reload a couple times before i get the page i requested. I'm behind a proxy-firewall, and the error is as follows: --start of errormessage-- 502 Proxy Error The WWW proxy was unable to forward the request to the destination server. Your client has attempted to perform a request in a manner not allowed by the HTTP protocol standard. --end of errormessage-- All versions of Mozilla (from M18 up, haven't looked at earlier versions) have this problem. I think it's a VERY annoying bug, and should be fixed as soon as possible. Reproducible: Always Steps to Reproduce: Use the browser behind a proxy-firewall, and request a page, any page. Actual Results: See above. (error message) Expected Results: It should have shown the requested page.

Reporter is this stil a problem in the latest nightlies?

Yes, i try the nightlies about once a week, and the problem is not going away. Right now i'm on build 2000121820, with the same problem.

I have been looking for the duplicate off and on all day today but can't find it. Therefore I am going to go ahead and mark it NEW.

Ok, thanks. This bug really keeps me from showing Mozilla to anyone else in my company. I hope it can be fixed soon. Note: I tried to reproduce this error with other browsers, to see if it has something to do with the proxy-server itself. I tried Opera 5.01, NS 4.75 and IE 5.5, and it looks like these all work correctly. NS 6 gave the same error as Mozilla, but that's no surprise. :-)

--> proxy bug

I'll sign up to analyze this problem... Do you know the vendor of the Proxy server you are using? Does this happen under certain conditions or a certain page?

Thanks. Sorry, but there's no way for me to know the type of proxy-server. The company won't tell me. :-) It's suspected that's it's some solution by Microsoft. (most things are around here) There are no particular conditions in which this happens or not. It seems to happen more often when i click a link or type in a new page when the current page hasn't finished loading yet.

I have noticed this bug too. Our company is using an NT proxy server. The error does not occur with Netscape 4, Opera 5, although I think I remember IE doing it once (or was I just imagining that?). Here's the message the server returns: 502 Proxy Error The WWW proxy was unable to forward the request to the destination server Your client has attempted to perform a request in a manner not allowed by the HTTP protocol standard. If you are using Microsoft Internet Explorer, make sure the "Use HTTP 1.1 through proxy connections" option is disabled, and click reload to try again. This error may also be caused by using MIE version 4 without Service Pack 2 (or HotFix #2798) installed.

Does anyone have a Microsoft Proxy I can test against? Also, exmamples need a sample URL, prefereably a public URL I could access ("I always breaks on www.news.com").

This sounds a lot like bug 38488 - can't use an HTTP/1.0 proxy like Junkbuster without changing debug prefs.

I think you're right! I just tried turning off the 'Enable Keep Alive' checkbox, and it now works nicely. I clicked through a LinuxToday-article with about 50 responses without waiting for the pages to load entirely. This went without any proxy-errors whatsoever. As soon as a turned the checkbox back on, the problems started showing again immediately. Looks to me like this bug is a dupe of that LOOOONG list of other bugs in 38488. If somebody could solve that particular bug, he'd probably become the Mozilla-hero-of-the-month for many people, i'm sure. ;-)

*** This bug has been marked as a duplicate of 38488 ***

Verified dupe.