ConfigMgr Restart Task fails if client has SUBST-ituted drive

Everytime I'm suprised when I see a new error during deployment in ConfigMgr. Today I have a new one for you. During a default "Restart Computer" step in a task sequence I get the following message. This on a server device running Microsoft App-V Sequencer software.

-Unable to get a handle to device Q: (0x80070005)
-Failed to convert Q: to unique volume id. Code : 0x80070005
-Failed to convert protected paths to unqiue ID. Error code 0x80070005
-Failed to reboot the system. Error 0x(80070005)
-Failed to initialize a system reboot. Permissions on the requested may be configured incorrectly.
-Unknown error (Error: 80070005; Source: Unknown)
-Fatal error is returned in check for reboot request of the action (Restart Computer). Permissions on the requested may be configured incorrectly.
-Unknown error (Error: 80070005; Source: Unknown)
An error (0x80070005) is encountered in execution of the task sequence

Lucky me I found the following blogpost: Microsoft TechNet
It mentions: The workaround we're using is to run a SUBST /D command line prior the restart step to make it work, but i was wondering if this is an accepted bug or limit of the software.

In my case I'm using a "Run Command Line" with "SUBST Q: /D" now to get the job done. No problem anymore during deployment!

Hope it helps!