Hi I have a setup of two servers, one is Exchange and the other is Data. Both runs W2k3 server. Both has to be Domain Controllers, so that if one fails, other takes over, etc... This setup worked very fine in the past. I came aboard, and I realized that one HDD is failing from the RAID 5 on the Data server. So I decided to upgrade them. I wanted to Demote the Server from being a DC, do the reinstall and then promote again. The Demote failed, so I did a force demote, and I replaced the drives, etc, reinstalled the server, and now I am trying to Promote it to be a DC, but it fails, with the same error as it failed with when I tried to demote it. The error is as follows, The operation failed because: The Active Directory Installation Wizard was unable to convert the computer account DATASERVER$ to a domain controller account. "Access is denied." What may I be doing wrong? I did a clean on the AD to remove the junk the old DC left behind, due to a not clean Demoting. i used the ntdsutil command to clean the AD from the DC's leftovers. All seemed fine. But, just to be certain, I tried to change the name of the server, and make it a DC with the new name, but it failed as well, so it isnt because the old one left junk there, as even new name wont go through. I think it is a permission issue, but i am not able to determine why and where is the problem. Please help if you can. thanks Benedek p.s. In addition to this, DNS entry is not correct also. I have DHCP enabled on the other Server (Exchange), but this has a static one of course. I can verify it, if I type ipconfig, etc. All is fine. But in DNS of the other server it shows up with a different IP, from the DHCP pool. When I delete it, it will recreate it in a small timeframe, with the same DHCP address. When I ping that given address, nothign responds, due to nothing is on that IP. Why would this happen? That DNS server is the DNS host of this newly reinstalled server. It should update just fine, like it does with all other machine. Strange...