Thanks for that. Updateng AD, do you think it will effect the small number of red hat and sun solaris boxes we have? Red hat is version 3as and 4as and Sun Solaris version 7 and 9. "Jorge Silva" wrote: So you're going to introduce windows 2003 DCs in your existing domain, I don't see any problem with that. IIRC you'll nee to upgrade the ADC. You can get more details in exchange