Hello,
We recently upgraded our Active Directory infrastructure from 2008 to 2012 R2. We performed all of the migration procedures and now have two 2012 R2 fully-replicating domain controllers. The only item left on the to-do list is to raise the functional level of the Domain and Forest to 2012 R2.
Prior to migrating to 2012 R2 we upgraded both the Domain and Forest to 2008 which was the highest OS we had at the time. Now that we're fully-migrated to 2012 I'm not able to raise the functional level on either the Domain or Forest past 2008 R2. When I go into the Domain or Forest Functional Level wizards it says that I'm on the highest functional level available.
The only thought I have at this point is that we didn't run ADPREP prior to migrating. This omission was done deliberately because of countless articles stating it wasn't necessary. Now I'm beginning to wonder if we needed to run ADPREP after all.
Question for forum: Can anyone explain why we can't raise the functional level of our Domain and Forest past 2008 R2 and does anyone think running ADPREP could resolve the issue?
Thanks in advance.