Thanks guys...
I tried all three of your suggestions and none of them removed the .net usernames and passwords, those found in run\control userpasswords2\advanced tab. But i did find out how to do it if your interested....
All you have to do is to "enable" the security option called "Network access: Do not allow storage of credentials or .Net Passports for network authenitcation"
You can find this option here....
run/gpedit.msc/computer configuration/windows settings/security settings/local polices/security options/
ONce you've done this the popup window asking you to get a .Net identity pops up when you go to start MSN messenger which can be stopped as well (after the intitial logon)....
Read this article in "The Register" to find out how to fix that little devil...
http://www.theregister.co.uk/content/archive/24668.html
Hybrid Mode
