Microsoft Hyper-V • Qualys vulnerability scanner VM and PAYLOAD_BLOCK_ZERO error

Attempts to take backup of a freshly-deployed (yesterday) Qualys vulnerability scanner appliance VM on HyperV result in the following error:

Processing QUALYS-HyperV Error: VHDx:CVhdxDisk.InitialValidation: Incorrect bitmap entry type (PAYLOAD_BLOCK_ZERO): See [MS-VHDX-v1.00-20160128] specification section 3.4.1.2. Agent failed to process method {VHDX.GetDiskInformation}.
Error: VHDx:CVhdxDisk.InitialValidation: Incorrect bitmap entry type (PAYLOAD_BLOCK_ZERO): See [MS-VHDX-v1.00-20160128] specification section 3.4.1.2. Agent failed to process method {VHDX.GetDiskInformation}.
Processing finished with errors at 25/09/2025 9:50:23 AM

Doesn't matter whether or not I have the VM powered ON or OFF. It is a fairly inconsequential VM and I can probably just shut it down and take a copy using Windows Explorer ... but ... I guess I am curious ... the VM runs fine ... am wondering if Qualys deliberately engineered this to prevent backup copies being made?

Statistics: Posted by Frosty — Sep 25, 2025 12:04 am

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