Exchange 2013 Readiness Check Error

Hello Everyone,

I am trying to do a new install of Exchange 2013 on a VM with SRV 2008 R2 SP1.

I am running the Setup wizard and getting the following error after the readiness check -

Active Directory must be prepared with 'Setup /PrepareAD' before domains can be prepared for Exchange 2010.

My AD and DNS seem to be all ok. I am using AD Ent credential. I looked at the Exchnagesetup log file and looks like PrepareaAD went through ok. It syas "PrepareAD has been run and replicated to this domain..".

Where it stopped is -

Failed [Rule:DomainPrepWithoutADUpdate] [Message:Active Directory must be prepared with 'Setup /PrepareAD' before domains can be prepared for Exchange 2010.

Anyone can suggest anything?

Also I must say I am relatively new  to MS environment.

Thanks.