After an official release of a Windows Embedded Standard 7 image you might to maintain your master image with updating your service packs without booting.
Step 1: After you have updated your repository with Windows Embedded Developer Update tool (WEDU) you need to create and updated Config-Set from your target (e: is the device where your Master Image is located):
pkgscn /Find-Updates /Image:e:\ /PackagePath:"C:\Program Files (x86)\Windows Embedded Standard 7\DSSP1" /ConfigSetDir:c:\temp\configset
Step 2: Apply Updatedes to your master image:
dism /image:e:\ /Apply-Unattend:"c:\temp\configset\AutoUnattend.xml"
Sometimes you might have a failure in your repository. With the following command you can recreate your repository index:
importpackage.exe /RebuildIndex "C:\Program Files (x86)\Windows Embedded Standard 7\DSSP1"