When you are done editing your vDisk in Provisioning Server, you will need to set the vDisk status back from “Private” to “Standard”. However, when you press OK the following error will appear: 
Cause
A bug in the Provisioning Server 5.6 console.
Solution
When you edit the properties of the vDisk set the disk status to Standard and select “MAK” on the Licensing TAB and press OK. Now you will not receive the error 
If desired, edit the properties of the vDisk again and select “KMS” on the licensing TAB and press OK.
This works if the disk is not in use, when adding the service account of the streaming/ soap service to local admin, restart the soap services, you can increase version to production without changing this option.
Regards
Verloigne Geert