Hello EE. We currentlh have our DCs running Win 2003 R2. We are in the process of updating some of our hardware the DCs being part of that. I am debating whether to run Win 2008 R2 on the new servers. Everytime Microsoft comes out with new versions of OS they remove, add, and change things from previous versions which isn't neccessarily a good thing thing (I realize it has been out for a while and has under gone a service pack upgrade). I was wondering if anyone who has upgraded from 2003 to 2008 experienced any undesirable effects.