Earlier I shrunk drive C using Disk Management but ran into "The parameter is incorrect" error. I now have the following situation:
According to the top pane in the following screenshot, Disk 0 (which hosts C: and System Reserved) should have 272.25GB - 156.25GB - 100MB = 115.9GB available:
But notice that volume C is reported as having 156.25GB in the top pane but 275.15GB in bottom. And I am unable to find the missing space. Where is the missing space and how do I get it back?