edwalt's - Things I Wish I'd known about SBS 2003....
Interesting case..... any user that was created with a template through the SBS Add User Wizard would receive the following error when trying to use Active-sync, "Error 85010014". However if you created a user directly in AD Users and Computers, that account could synchronize without an issue. Experienced the same problem when creating test users with each of the different templates. Must be a template issue.... right?? ......Well
Let me give you some additional information
Rule #1 - When troubleshooting Active-sync, especially Mobile 5 technology always insure that Exchange SP2 is installed. this update has alot of fixes that revolve around active-sync.
The issue actually turned out to be an IIS issue.
Open IIS - Open websites - click on Default Website. The paths of the sub-sites will appear on the right hand side of the screen.
Exchange Path = \\.\BackOfficeStorage\abcefghij.com\MBX
Exchange-Oma = \\.\BackOfficeStorage\ABC.local\MBX
The Exchange-Oma path should match the Exchange path in order for synchronization to work. I copied the Exchange-Oma path out to notepad, and then copied the path from the Exchange path into the Exchange-Oma path in IIS. Ran iisreset, tested synchronization again and it worked.