Hi
I can say all I have had is a bad experience with this extension. There has been for me a performance bug in this and it has caused me no end of grief when it gets installed in FF. I am no fan of Microsoft at the best of times, but that was a bad idea from them and it took a while for them to do something about it. I initially had disabled it, then finally I removed it from 3.5 after Microsoft made it possible to remove it
I upgrade the other day to 3.6 RC2 and found the it had snuck back in and cannot be removed from the 3.6 installation from the add-ons screen. I eventually found this and have taken it out completely from my system.
Interestingly I have a .Net 3.5 update in Windows updates this morning so after I post this I will be rebooting to install that and will be seeing if the product is back on disk and if it tries to reinstall itself in FF.
Unfortunately it is also associated with a known long standing Windows bug that is in IE, it may be fixed but with the history of IE bigs I would be wary. http://blog.mozilla.com/security/2009/10/16/net-framework-assistant-blocked-to-disarm-security-vulnerability/
MS has advised that this should be safe but the said that about IE a lot of times.

How to remove the .NET Framework Assistant for Firefox

Have a safe day surfing

Peter

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