How to upgrade VMware VirtualCenter 2.5 SQL Express to SQL 2005:

1. Step 0: BACKUP or SNAPSHOT your VC server!
2. Stop VirtualCenter service
3. Stop VMware Update service
4. Stop License Server service
5. Stop SQL Express service
6. copy the SQL data files to the new SQL 2005 location. Example below:
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8. on the new SQL 2005 server, start Management Studio and use "attach database" function import the migrated data files. Name the new database VIM_VCDB (or any other name).
9. identify or create a SQL user (vmware is recommended, but anything will work) on the SQL 2005 server to have db_owner role for the VIM_VCDB database.
10. on the VirtualCenter server, modify the both of the VMware DSNs in "Administrative Tools -> Data Source (ODBC)", see below:
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15. take defaults for the rest of the steps.
16. Edit registry key "HKEY_LOCAL_MACHINE\SOFTWARE\VMware, Inc.\VMware VirtualCenter\DB\2" with the SQL user name.
17. at cmd prompt, run "vpxd -p" from the VirtualCenter folder under "c:\Program Files" (or the equivalent) and supply the password.
18. start Licensing Server
19. start VMware Update Manager
20. start VirtualCenter Service
21. test connection and functionality from a VI Client and you are done. if it works with no glitch, pat yourself on the back!