Summary: Use Windows PowerShell 3.0 in Windows Server 2012 or Windows 8 to resize partitions.
How can I easily resize partitions in Windows Server 2012 or Windows 8 by using Windows PowerShell 3.0?
Microsoft PFE, Jason Walker, says, “Use the Get-PartitionSupportedSize and the Resize-Partition functions:"
$MaxSize = (Get-PartitionSupportedSize -DriveLetter c).sizeMax
Resize-Partition -DriveLetter c -Size $MaxSize