I opened the Windows event log viewer and found several errors of VSS.
One of them was Event ID 22 -
Volume Shadow Copy Service error: A critical component required by the Volume Shadow Copy service is not registered. This might happened if an error occurred during Windows setup or during installation of a Shadow Copy provider. The error returned from CoCreateInstance on class with CLSID {79079d5c-ef20-4952-b9fc-cfd443b38641} and Name SW_PROV is [0x80040154, Class not registered].
Run RegEdit and open the registry path
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\services\VSS\Providers
There was a registry key of {f782463b-33bb-4043-ad8d-60b728d26a6c} that represented as "Acronis VSS SW Provider" and there was a CLSID item of {79079d5c-ef20-4952-b9fc-cfd443b38641} under it.
The backup software Acronis is no longer installed on the server. After I deleted the registry key of {f782463b-33bb-4043-ad8d-60b728d26a6c}, Disk2VHD worked perfectly.
Hopefully this information can save your time.
