Exchange Backup

As for AD: you need to do a system state backup of a DC to properly get a valid backup of AD.  So restoring AD to a different OS isn't an option due to having to restore the system state.  You'll need to restore to the same OS version.

As for Exchange:  (disclosure: I am not an exchange specialist) you cannot just restore an Exchange 2010 datastore to an Exchange 2013 system.  Typically you have to deploy Ex2010 Servers and Ex2013 Servers in parallel and migrate users using PowerShell.

In your scenario, there would be AD object missing since you need to do a domain prep before deploying Ex2013 in your domain.  Meaning, trying to restore a 2008 AD database over a 2012 system would wipe out any Exchange 2013 prep work done to the AD system.  Therefore rendering the Exchange 2013 deployment inoperable or at least with a ton of errors and a lot of headaches.

Dan

migration should create too many errors depending on per mail sizes, user rights ....... etc.

If we first upgrade to 2012 server then we get the backup of active directory should we install it to a newly installed server 2012 ?

Migration will not create too many errors.  I am in the middle of a Ex2007 to Ex2013 migration and moving users just requires the user to log off, back on and open Outlook.

If you upgrade the DC to 2012 (which I do not recommend) why would you backup and restore to a different server?

What is it that you are trying to accomplish, in the bigger picture?

Dan

we are testing on virtual machines and created some kind of errors , we just want to have clean active directory and clean exchange.

Ex 2013 after upgrade some accounts wil probably have problems , we had issued tons of problems like
localization problems
blank page on owa
ecp send connecter problems
....etc

we tested on CU6 it still does not support any language expect english. if sth. different then english in localization it give strange logs that nothing point to real problem

Thank you