Hyper-V client plugin is empty and cannot be expanded (4047908)

Date: 30/11/2010
Product & Version: NVBU 8.5.2
OS Version: Windows 2008
Module & Version: Hyper-V plugin
Application version: Hyper-V

Symptoms 1:
Backup fail and when browsing the plugin, the plugin does not expand beyond localhost and no virtual machines are shown.

- On the HyperV server, in powershell trying to run the GetVM.ps1, you get the following error:
PS C:\Program Files (x86)\Quest Software\NetVault Backup\scripts\HyperV> .\GetVmFileList.ps1
Unable to load file C: \ Program Files (x86) \ Quest Software \ NetVault Backup \ scripts \ HyperV \ GetVmFileList.p
s1, for the execution of scripts is disabled on this system. For more information, see "get-help about_sign
Eng.
At line: 1 char: 20
+. \ GetVmFileList.ps1 <<<<
+ CategoryInfo: NotSpecified: (:) [] PSSecurityException
+ FullyQualifiedErrorId: RuntimeException

PS C: \ Program Files (x86) \ Quest Software \ NetVault Backup \ scripts \ HyperV>. \ GetVms.ps1
Unable to load file C: \ Program Files (x86) \ Quest Software \ NetVault Backup \ scripts \ HyperV \ GetVms.ps1 because
the execution of scripts is disabled on this system. For more information, see "get-help about_signing.
At line: 1 char: 13
+. \ GetVms.ps1 <<<<
+ CategoryInfo: NotSpecified: (:) [] PSSecurityException
+ FullyQualifiedErrorId: RuntimeException

Symptoms 2 :

Customer reports they are unable to see virtual machine in HyperV Host.. Error message shown: Unable to parse output of \scripts\HyperV\Getclusterhosts.ps1