When importing vDisk, the following error appears:
“Invalid disk file for [vDisk name]. Cannot add disk”

After clicking OK, the following error appears:
“The scan did not find any new vDisks”

Rename the .vhd file in the vDisk store and import the vDisk using the Add or Import Existing vDisks. This process cannot be done if vDisk versions exist.
Note: vDisk with the same name cannot be imported in the same Provisioning Service farm.

Problem Cause

While copying and importing the .vhd file to be used in another Provisioning Service vDisk store, the original file cannot be imported using the Add or Import Existing vDisks option. The .vhd file name must be renamed to be imported successfully.
Another probable cause is a corrupted .pvp file, in which case it should be recreated.

Citrix eDocs - Exporting and Importing vDisks