“Windows is unable to verify the image integrity of the file MfApHook64.dll” in the Event Log

Solution 1

If additional LSA protection is configured, you must upgrade the VDA to the following versions:

  • Single-session desktop OS
    • Explicit and FAS authentication: Virtual Apps and Desktops 1906
    • Smart Card Authentication: Not supported at the moment. Support will be added in a future release.
  • Multi-session server OS: Additional LSA protection is currently not supported on this platform. Support will be added in a future release.

Solution 2

If additional LSA protection is not configured, these events can be safely ignored because they do not adversely affect functionality of any Citrix component. This issue has been investigated and it was determined to not be a Citrix issue. The MfApHook64 DLL is signed correctly.

The validity of the MfApHook64 DLL signature can be verified on the VDA by using Windows Explorer, navigating to ‘C:Program FilesCitrixSystem32’ (on a single-session desktop OS VDA) or ‘C:Program Files (x86)CitrixSystem32 (on a multi-session server OS VDA), selecting the MfApHook64.dll file, right-clicking and choosing Properties and selecting the Digital Signatures tab.


  • No Related Posts

Leave a Reply