I had a previous question answered regarding a client migration I'm doing. I'm doing some testing with VMs of the client servers in my test network for the migration in a few months.
I've read some conflicting instructions and I'm hoping someone can clear up the confusion.
The 2003 SBS box is running at the 2000 forest and domain functional levels. I had to raise them to the 2003 to allow the 2012 box to join as a DC. The only change I made was in the AD Users and Computers and the AD Domains and Trusts on the 2003 SBS box. I right-clicked and selected to raise both levels to 2003. After that, it allowed me to DCPROMO the 2012 Standard box. It appears to have worked, but now I'm reading that I should've run ADPREP to upgrade the schema before even promoting the 2012 to a DC.
I'm just curious if this is the case for the upgrade process? If so, have I already made a mistake in running the DCPROMO on the 2012 box? The SBS 20003 box is running exchange, which will be going away as they are transitioning to Office 365. I have read several articles on that and everyone recommends uninstalling exchange and then DCPROMOing the 2003 SBS box out of the network.
Any help would be greatly appreciated. Thank you!