You can follow:
Q260378 XADM: How to Manually Remove an Exchange 2000 Installation
which can be found at:
I'm running BackOffice SBS, and I need to uninstall Exchange.
When I try through ADD/REMOVE, I get and error "An error
occurred while trying to remove MS Exchange" Uninstallation
has been canceled. Any help or idea's would be GREAT...
Thanks in advance...