576614 - Firefox not working with some web servers (error 501 - Method not implemented)

Status: RESOLVED INVALID

(Firefox :: General, defect)

Description

[cubicdesign]

User-Agent:       Mozilla/5.0 (Windows; U; Windows NT 6.1; en-US; rv:1.9.2.6) Gecko/20100625 Firefox/3.6.6
Build Identifier: Mozilla/5.0 (Windows; U; Windows NT 6.1; en-US; rv:1.9.2.6) Gecko/20100625 Firefox/3.6.6

Hi. I have a web site hosted at IMotion Hosting. From time to time I see a 501 error message from their server. Visitors reported exactly the error too.

The message is:
"501 - Method not implemented"

Sometimes it comes with additional error messages such as 502 and 404:
"Method Not Implemented

GET to /forum/ not supported.

Additionally, a 404 Not Found error was encountered while trying to use an ErrorDocument to handle the request."

The bug cannot be reproduced on demand. Once it appears it never goes away. Later I have discovered that sometimes, when it appear in FF it may also appear in IE.

The host (InMotion Hosting) says it is a FF bug:
"The IP itself isn't listed or blocked, only the excess (or improper) connections to the web service are rejected.  Much like the thread you were referring to previously, this can also be caused by utilizing HTTP 1.1 if the protocol isn't supported on the local PC, remote end, or in some cases Proxy/Network settings.  While the most common sets of instructions are provided for Internet Explorer versions, this can also be modified in Firefox in the about:config screen (see the following pages for more information)

http://kb.mozillazine.org/Editing_configuration
http://kb.mozillazine.org/Network.http.proxy.version

If you're able to access your site through another computer on your network, or outside the network, this might be indicative of a local setting or configuration issue (or even influences outside the browser such as a firewall).

Best Regards,

David D.
[e-mail]
"

Reproducible: Sometimes

Steps to Reproduce:
1. Start browser and 
2. quickly control-click several links to open them in new tabs
Actual Results:  
All tabs loaded ok but when I tried to refresh one of them, the browser returned a 501 message.

Expected Results:  
My web site

I think the only way to make the browser work again is to clear its cache and especially the cookies. There are mixed results though. It seems to work only sometimes.

Comment 1

[cubicdesign]

It works in "Private browsing" mode.
So, I would say now it is a Firefox bug.

Comment 2

[cubicdesign]

It is not a Mozilla bug. Sorry.


"I sincerely apologize about the delay in getting back to you regarding this issue. I have reviewed this issue throughly and have come to the conclusion that this 501/505 error is due to your domain having mod_security enabled. I have since disabled this apache module for your domain bionixwallpaper.com and you should no longer experience this problem."