First delete all VSS snapshots (e.g. disk F):

vssadmin delete shadows /for=f: /all

Optimize the disk with powershell:

Optimize-Volume -driveletter F -defrag -verbose

Resize the disk with powershell (e.d. to 450 GB):

Resize-Partition -Driveletter F –Size 450GB

Shrink the disk with diskpart (e.d. 1784 MB):

shrink minimum 1784

To check the Maximum size and the Minimum size to where a disk can shrink, use the following command:

Get-PartitionSupportedSize -DiskNumber 1 -PartitionNumber 1 | select @{Name=”Minimum Size (GB)”; Expression={$_.SizeMin/1GB}}, @{Name=”Maximum Size (GB)”;Expression={$_.SizeMax/1GB}}

With Diskpart

shrink querymax