Caution! Refer to the Disclaimer at the end of this article before using Registry Editor.

The issue can be reproduced as follows:

2. Apply the following registry key 
   HKLM\SYSTEM\CurrentControlSet\Control\FileSystem 
   Name: NtfsDisable8dot3NameCreation 
   Datatype: Reg_Dword Value:1

3. Run XenConvert on the newly installed server and create a Provisioning Services virtual disk.

4. Check on the XenApp 6.5 Provisioned Target Device with the Microsoft Process Explorer for DLLs mfaphook.dll and mfaphook64.dll.

   

There are no processes using mfaphook.dll and only spoolsvc.exe using mfaphook64.dll. In a working environment the situation is different. (Refer to the following images.)

To resolve the issue, complete one of the following instructions:

• Modify the following registry key and reboot the server.

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows NT\CurrentVersion\Windows "AppInit_DLLs"="C:\PROGRA~2\Citrix\System32\mfaphook64.dll" HKEY_LOCAL_MACHINE\SOFTWARE\Wow6432Node\Microsoft\Windows NT\CurrentVersion\Windows "AppInit_DLLs"="C:\PROGRA~2\Citrix\System32\mfaphook.dll" 

Or

• Recommended: Rebuild the server and apply registry key NtfsDisable8dot3NameCreation or XenApp Optimization Best Practice after XenConvert Tool.

Problem Cause

After installation of XenApp Server 6.5, the following registry subkey is set: 
HKLM\SYSTEM\CurrentControlSet\Control\FileSystem 
Name: NtfsDisable8dot3NameCreation 
Datatype: Reg_Dword Value:1

Note: This registry key is recommended in the XenApp Optimization Best Practice Guide.
And the virtual machine is converted to Provisioning Services. Users cannot use published applications.

CTX131577 – XenApp 6.x (Windows 2008 R2) - Optimization Guide
Additional information on the Microsoft registry key – Additional Registry Entries

The default value in a freshly installed Windows 2008 R2 Server is: 
HKLM\SYSTEM\CurrentControlSet\Control\FileSystem 
Name: NtfsDisable8dot3NameCreation 
Datatype: Reg_Dword Value:2