Just recently installed Windows 2003 Enterprise Edition with SP1 as my only server -- so it is theDomain Controller. Everything is running fine with no errors. I then installed Exchange 2003 a day later on the same machine and that too has no problems. A day later I attempted to update Exchange to SP1 by following these steps: 1) Start Windows Explorer. 2) Navigate to the \setup\i386 folder on the SP1 media (e.g, CD-ROM, folder). 3) Run update.exe. 4) Click Next on the SP1 installation dialog box's welcome screen. 5) Select "I agree" and click Next. . . . on the next screen I select the "Update" action and immediately upon that selection I get the following error: ---------------------------------------Microsoft Exchange Installation Wizard---------------------------------------The component "Microsoft Exchange Messaging and Collaboration Services" cannot be assigned the action "Update" because: - The Active Directory schema is not up-to-date. You must run setup with the "/ForestPrep" switch. If you have already done this with the current version of Setup, then you must wait for replication to complete. Consult your documentation for details. - The local domain configuration is not up-to-date. You must run setup with the "/DomainPrep" switch within this domain. If you have already done this with the current version of Setup, then you must wait for replication to complete. Consult your documentation for details. I ensured that: -- I ran both ForestPrep and DomainPrep prior to the original Exchange install (confirmed this following MS article 274737 (http://tinyurl.com/eylw7))-- I amrunning the update under an account that is a member of the Enterprise Administrators, Schema Administrators and local Administrators groups-- Windows Management Instrumentation service is running per MS article 824112 (http://tinyurl.com/3ch4x3) -- Running Replmon showed no errors How do I get past this, resolve this issue or satisfy the requirement?? What am I doing wrong??

Well, it appears that I was taking the right steps but there ended up being a problem with the Exchange CD I used to do the install (MSDN version) that lead to the issue(s) above. I ended up reinstalling and using an alternate software CD that worked without incident. I wonder if there is a compatibility issue across different versions of Exchange software. Both copies are Enterprise. Exchange SP2 has now been loaded successfully.