Firefox Illegal Character Error

[Bonjour_Rodney]

OK guys please help here. I'm going to go nuts if I can't figure this out.

I have two accounts on my PC.

1 My account setup as administrator

and

2 My fiancee's setup as a limited user.

OK, I am a huge American Football fan and as such I use NFL.com all the time to watch highlight videos etc. However videos will no longer play back from the web site and every time I try the error console report in Firefox reports an illegal character error. See below.

Error: illegal character
Source File: http://js.adsonar.com/js/adsonar.js
Line: 1, Column: 6
Source Code:
GIF89a


I have tried reinstalling firefox, Java, stopping plugins and extesions in logical sequence but the problem persists.

The more annoying thing is that the other limited user account plays the videos back fine and when I checked the error console, no errors are present!!!

PLEASE HELP.

I'm running Windows 7 BTW.

 

[Pho]

Easiest solution is probably to install Adblock Plus - using the Easylist (probably default) ad list it blocks adsonar adverts which should block that file from loading/erroring.

 

[Bonjour_Rodney]

Well well well. It was Kaspersky Internet security 2011. Re-installed it and now it works. Woo hoo Football time