dcpromo - can't promote new 2008 R2 server to DC

Posted on 2010-09-01
Last Modified: 2012-05-10
I currently have 2 DC's, one is Server 2k8 (32-bit), the other is Server 2k8 - 64 bit.  I am ready to retire the 32-bit DC, so I installed another Server, 2K8 R2 and am trying to promote it.  When I do, I get the error that I must first run adprep /forestprep on the FSMO host.  But my Domain functional level is already 2008, so shouldn't the forest already be ready for another 2K8 DC?  I am hesitant to run adprep unless I am sure it's the correct move.   I could use some guidance here.  Thanks
Question by:dvanaken
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LVL 57

Accepted Solution

Mike Kline earned 300 total points
ID: 33580226
Since you are using 2008 R2 you need a schema update.  

Is the box that holds your schema master x32 or x64

There are two versions of adprep in 2008 R2

adprep32 (for x32)
adprep (for x64)

Jon has a blog on that here

LVL 57

Expert Comment

by:Mike Kline
ID: 33580234
by the way you can quickly find your schema version using adfind from MVP Joe Richards

adfind -sc schver

Schema versions =
13 = windows 2000
30 = windows 2003
31 = windows 2003 R2
44 = windows 2008
47 = windows 2008 R2

LVL 96

Expert Comment

by:Lee W, MVP
ID: 33580241
Server 2008 R2 is NOT the same as Server 2008 - you have to do what the message says and upgrade the Schema - there is a folder on the DVD with ADPREP...
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Author Comment

ID: 33580242
All FSMO roles are on the 64-bit DC.  Should I go ahead and run adprep /forestprep on that box?

Assisted Solution

insightcomputing earned 200 total points
ID: 33580243
Runt he following TWO commands within the windows server 2008 cmd prompt:

ADPREP /forestprep

ADPREP /domainprep

Put your windows 2008 R2 64 bit disc into your old server, browse to the ADprep folder on the disc. Run the ADprep 64 bit version on your 2003 server (im assuming you have 2003 server) this will take some time, after it is finished, it may want a reboot. Reboot the server and then try to DC promo the machine again and let me know what happens.
LVL 57

Expert Comment

by:Mike Kline
ID: 33580264
All FSMO roles are on the 64-bit DC.  Should I go ahead and run adprep /forestprep on that box?

-- yes

Author Comment

ID: 33580366
Schema is happily converting from 44 to 47.  I'm not clear - do I need to run adprep /domainprep /gpprep as well?

Author Closing Comment

ID: 33580788
Thanks guys - much appreciated.

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