Hi, I have an NT4 Exchange 5.5 system that I need to upgrade as part of a whole domain/network upgrade. I plan on doing the other PDC/BDC first as in-place upgrades and then when that is done: Do the in-place upgrade of the NT4 to Win2K on the Exchange 5.5 Server (let it run as 2000/5.5 until the next weekend) Then do an in-place upgrade of the 5.5 to 2000 Any special considerations for this other than the regular backup everything before you do the upgrade? Thanx Goran Jovanovic The LAN Shoppe 2345 Yonge Street, Suite 302 Toronto, Ontario M4P 2E5 Phone: (416) 440-1167 x-2113 Cell: (416) 931-0688 E-Mail: gjovanovic@xxxxxxxxxxx