406 error Not Acceptable

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EDIT: ggppdk, you posted before me while I was writing


This may or may not have anything to do with FLEXIcontent.

In your first post the error message appears to tell us this is an issue with a cookie,
and that the cookie contains 0=0 ( [data "0=0"] ).
Apparently the mod_sec rule does not like that pattern of data.

A search on the internet for that error code reveals the same or similar error messages with many types of websites - including Joomla, WordPress, ecommerce, others CMSs, etc.
So this could also be an issue with a browser hijack, a bad browser plug-in, an infection on your system, etc., etc.

There were some other examples found in my search where a cookie with "1=1" triggered the rule.

The cookie could come from a number of different sources.
Joomla, Joomla extension, JavaScript, browser plug-in, etc. ...

Need to look at the contents the cookies for that website on your system.
Then it may be possible to tell if this has anything to do with FLEXIcontent.

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Thanks for the input. Now a couple hours later, I can't seem to get the mod-security to kick in. I am suspecting an infection on my pc.
I ran spybot s&d (removed a bunch of tracking cookies. Ran hijack this and removed a bunch of BHOs. Of course, I did that yesterday as well. But didn't remove so many BHOs. Today I removed a mystery startup process in the task manager as well.
The firefox extensions I have installed are:

firebug
download status bar
google voice.
google disconnect.(disabled)

I installed the web dev plugin: No cookies showing the 0:0 now!?

The site is simply for testing flexicont and only a few components (flexi, jce, xmap) and plugins are installed. The plugins I have been trying in flexi are googlemaps by mike reumer and sigplus from levante h. I was working on triggering the plugins in a field as well as tweaking the templates when this started.
In addition, rizvn login module and Brute Force Stop plugin by bernhard f and cache cleaner by peter vw. I have gotten the 406 with these disabled and enabled.

rockettheme theme -- fracture.

Thanks for your support. Ken I have watched your posts on joomla for years. Seeing your presence here adds to this project as well! thanks!! Excuse me for going on, but I want to be thorough.

Just getting ready to shut down and hit save and return in the front end and got a 404 error with this in the url bar ...//mysite.com/http%3A%2F%2Fmysite.com%2F :evil: obfuscating the site as I don't want a bunch of people pounding it. send a pm if you want a login.

Then thought I would test trying to add a new item in the backend got the 406. :evil:

No 0:0 in the cookies and nothing showing yet in my whm mod sec log.

If I disable mod sec. the site to loads
Re enable mod sec and remove all cookies the site to loads.

Yes you can send a PM to me

I tested in your site but i am not getting the 406 error by mod_security

grantiago,
It appears the issue is your system is still infected.