RIS services fails to start with Error 127: the specified procedure could not be found error

This occurs after installing Windows 2003 SP2. The reason for this is that the new Windows Deployment Services (to allow Vista images to be made) is installed, and then is put in charge of the RIS deployment, rendering the Remote Installation service obsolete. To fix this, run services.msc and make your RIS service startup type to be manual or disabled, and select Windows Deployment Services to be automatic. You can then boot into the pre execution environment as normal and your old images will be there. See HERE for more information.