we apreciate your help... best regards!!
closed as not a real question by Mark Henderson♦, Zypher♦, duffbeer703, Nick Kavadias, Jim B Feb 10 '10 at 2:20
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Forget Active Directory, Look at DNS
It's not a particularly nice solution if you have a lot of them to block. Still possible though. Hopefully this explains how.
If you want to block entire domains you would:
If you just want to block websites under domains you do almost the same:
This way, you could still send mail and access other resources as annoyingdomain.com, it's just the address for www.annoyingdomain.com which gets answered by your own DNS Server.
Like I said, not exactely a nice solution, but, if you just want to block a few sites like myspace of Facebook, and dont have the money to spend on an Appliance as Wesley Recommended
Although I will say an appliance is the better solution
Use Group Policy to edit IE's Content Advisor settings. You may need the ADM templates for IE. However, that will only work for Internet Explorer settings so you'll have to block all other browsers somehow. Really, your best bet will be an appliance (E.g. Websense) or proxy server (E.g. Squid Cache).