Well this is just as annoying as can be but it turns out to be pretty quick to resolve.  If you reboot your client PC’s but find some software you pushed via Group Policy did not install, you likely are in Asyncronous Policy Processing Hell.

First verify that the policy did make it to your test PC by launching a CMD window (don’t forget to RUN AS ADMINISTRATOR) and typing GPRESULT.  Just look for your GPO under COMPUTER.  Also check the event log of your test PC and look for The error was : %%1274

BACKGROUND:

Since Windows Server 2003, XP and newer clients don’t wait for the network components to fully load before allowing a user to login.  This makes boot times faster but means that Software Deployments via Group Policy almost always require TWO reboots.  Also, you can get the dreaded:

System Event 108 “The error was : %%1274”

and never get an install completed.

SOLUTIONS:

1. Delete the GP Key from the client PC’s registry: HKLM/SOFTWARE/Microsoft/Windows/CurrentVersion/Group Policy
2. Turn Asyncronous Policy Processing off by creating a new GPO (or editing an existing one) with the following setting:
   Computer Settings > Administrative Templates > System > Logon > Always wait for the network at computer startup and logon – Enabled

I figured this out using several blogs but the most useful and the one deserving the most credit is THIS ONE, in case you want to read more about it.