In any layer, when creating it, you must double-click on the Shutdown for Finalize script, where we determine that there are no pending Windows operations that need to complete before we finalize.  When you run this, you may see this:

Layer Finalize is BLOCKED, The outstanding items are: 'a RunOnce script is outstanding - please check and reboot the packaging machine.

 

The script error message is telling you that it has found a script listed here:

HKLM\Software\Microsoft\Windows\CurrentVersion\RunOnce\

Scripts listed there will run whenever the build-in Administrator account runs (this is how Windows works, it's not an App Layering requirement). You should first try rebooting and see if the script runs and the registry key is cleared.

However, if your built-in Administrator account is deleted, it may be that RunOnce scripts never run.  App Layering actually puts a specific script in as a RunOnce key whenever it publishes an image, which we need to run the first time your Packaging Machine runs.  So if RunOnce keys are effectively blocked because your security policy requires you to delete or otherwise defeat the built-in Administrator account, you will always see this.

The script App Layering is putting in RunOnce is this:

UniEnvSetup="C:\Program Files\Unidesk\UniService\envsetup.cmd

If rebooting does not clear this, you must delete this registry key by hand.  Please also run envsetup.cmd once as Administrator.

In any layer, when creating it, you must double-click on the Shutdown for Finalize script, where we determine that there are no pending Windows operations that need to complete before we finalize.