If you enable mount point and partition discovery with the latest Server OS Management Pack, you may see a \\?\Volume{xxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxx} Alert show in the console. From what I have found, this is due to the 100 MB System Reserved partition getting discovered.  You can tune this alert, or create an override to help tune this out of the console.
These steps below will help you to tune the \\?\Volume ID from being discovered or monitored for disk space.
Alerts showing in the Console:

Create a new Dynamic or Static Override Group to look for \\?\Volume and exclude this from monitoring:
1.      From the Authoring View, right click Groups, ‘Create New Group’
2.      Name the Group a name in which you can easily identify where the Overrides are Targeted
·        I used ‘Disk Monitor Disabled Override Group’ or you could use \\?\Volume in the name
·        Create an Override Groups MP and save the New Group in this MP

3.      To Create a Static Group (If you want to manually control which objects are excluded): at the Explicit Members page, search for \\?\Volume, then add all objects found for each Computer to the Group, click OK.



4.      To Create a Dynamic Group (Do not use the Explicit Members option): at the Dynamic Members page, click New, then Insert the property for the following and click OK:
·        AND group for Logical Disk (all of these are true)
·        Display Name – Contains – \\?\Volume


5.      Create an Override to target the new Group you created above
·        Monitor Name – Windows Server 2008 Logical Disk Free Space (MB) Low
·        Override the Enabled Value, and click Enforced

6.      Create an Override on the Mount Point Discovery Rule in Object Discovery for the Group created in the steps above to disable the Discovery of the System Reserved Partition
7. Right click the Mount Point Discovery rule, click Override > Override for Group, then Click Override, False , Enforced, click OK