This week I upgraded a production environment of Configuration Manager 2012 to Service Pack 1. After the upgrade our 4 remote Distribution Points failed to service PXE. It seemed that the Windows Deployment Service was not able to start.
Looking at the local event viewers learned me that several errors like event id 257, 259 and 264 were there which pointed me to an issue described here where the Microsoft Visual C++ 2008 Redistributable on the remote distribution points were missing. Unfortunately it did not work out for me since both the x86 and x64 version of the Microsoft Visual C++ 2008 Redistributable were already in place.
Everything else was just working great and health after the upgrade was finished.
Read the complete blog here: http://configmgrblog.com/2013/02/27/pxe-on-remote-dps-failed-after-upgrade-to-configmgr-2012-sp1/