8dot3 short file name setting is disabled on the converted volumes after P2V.

Problem

8dot3 short file name (8dot3name) setting is disabled on the converted volumes after P2V to Windows 2012 or Windows 2012 R2 Hyper-V host.

The following result is returned when running "fsutil 8dot3name query c:" on the original system.
8dot3 name creation is enabled on the original system.
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C:> fsutil 8dot3name query c:
 The volume state is: 0 (8dot3 name creation is enabled).
 The registry state of NtfsDisable8dot3NameCreation is 2, the default (Volume level setting).
 Based on the above two settings, 8dot3 name creation is enabled on c:.
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However, the following result is returned when running "fsutil 8dot3name query c:" on the converted virtual machine. The volume state is 1 and 8dot3 name creation is disabled on the converted virtual machine.
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C:> fsutil 8dot3name query c:
 The volume state is: 1 (8dot3 name creation is disabled).
 The registry state of NtfsDisable8dot3NameCreation is 2, the default (Volume level setting).
 Based on the above two settings, 8dot3 name creation is disabled on c:.
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Note: This issue occurs when converting to Windows 2012 / Windows 2012 R2 Hyper-V host, and it never occurs under the following conditions.

1. when converting to VMware ESX/vCenter (VMDX) host.
2. when using SDR.
3. when converting to Windows 2008 R2 Hyper-V host.

Cause

This issue is caused by the conversion to Windows 2012 / Windows 2012 R2 Hyper-V host.

In general, when adding a new VHD/VHDX to the existing virtual machine on Windows 2012 / Windows 2012 R2 Hyper-V host using Hyper-V manager, the VHD/VHDX is created with the disabled 8dot3name. Similarly, when performing P2V to Windows 2012 / Windows 2012 R2 Hyper-V host, P2V by Backup Exec creates a new VHD/VHDX with the disabled 8dot3name.

For reasons or details of disabled 8dot3name setting, please refer to the following blog by Microsoft.

https://blogs.technet.microsoft.com/josebda/2012/11/13/windows-server-2012-file-server-tip-disable-8-3-naming-and-strip-those-short-names-too/
 

Solution

This is by design.

WORKAROUND:

Please perform either 1 or 2.

1. Perform SDR if 8dot3name setting needs to be enabled on the Windows 2012 / Windows 2012 Hyper-V virtual machine. The SDR enables 8dot3 short name creation.
2. Run the command "fsutil 8dot3name set 0" or  "fsutil 8dot3name set c: 0"