Adventures when upgrading SCCM 2012 to SP1

I recently upgraded our newly installed SCCM 2012 RTM infrastructure to SP1 after it's release in late December and after doing so I encountered a number of issues, below are the issues that I experienced and the associated fixes.


Broken MDT Database Connectivity

We have MDT 2012 U1 integrated with our SCCM infrastructure and use the MDAC based database functionality to lookup various details but after the SP1 upgrade,  the following errors could be found in the BDD.log;

Unable to create ADODB.Connection object, impossible to query SQL Server: ActiveX component can't create object (429)

After some research and forum posts I managed to confirm that the upgrade process had removed MDAC from the MDT Boot Image and therefore crippling database connectivity when inside WinPE. To resolve this, I found it necessary to recreate the the MDT Boot Image from within the SCCM Admin Console.


Misassignment of drive letters during OSD of Windows 7

Another side effect of the SP1 upgrade was that previously working Windows 7 images were installing but assigning drive letters D: or E: instead of the normal C: drive assignment. This appears to be a result of the introduction of the new Task Sequence variable OSDPreserveDriveLetter. When investigating my existing Task Sequences I found that a new step had been added to named 'Set Variable for Drive Letter' which declares the value of this variable as False. By changing this value to True, this ensures that the intended drive letter assignment is honoured and therefore future OS drives are assigned C:.