MS Volume Shadow copy Service H/W provider issue

hello,

I am trying to run MS Volume Shadow copy Service
Hardware provider sample code which is with VSSSDK 7.2 .But I am
getting the "VSS_E_UNEXPECTED_PROVIDER_ERROR" error at
addtosnapshotset() which is method of requestor.I tried the same on
both VMware and normal machine but error was same. I tried same by
passing H/W provider id to addtosnapshotset() then also it is giving
error.

How to use MS VSS H/W provider ?
Is there any special method for MS VSS H/W provider Registration or
loading ? OR
Is there any different volume name format MS VSS H/W provider ?

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