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Old 10-23-2018, 07:04 PM
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jdev jdev is offline
VanDyke Technical Support
Join Date: Nov 2003
Location: Albuquerque, NM
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Lightbulb KB: VShell for Windows - Public Key LSA Module

In order for public-key only authentication to be possible with VShell for Windows, A) VShell's "LSA Module" must be installed and B) the LSA module must be loaded by the Windows operating system.

A) Verifying the LSA Module is Installed
To determine if the LSA Module has been installed:
  1. Verify that there is a "vdspka10.dll" file in Windows' System32 folder

  2. Verify that the following registry REG_MULTI_SZ value contains "vdspka10":
    HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Lsa\Authentication Packages

    WARNING: Do not attempt to manually edit this registry key! Only verify that vdspka10 is listed in the value. For example, run the following command within an Administrator:CMD window:
    REG QUERY "HKLM\SYSTEM\CurrentControlSet\Control\Lsa" /v "Authentication Packages"

    Expected output:
        Authentication Packages    REG_MULTI_SZ    msv1_0\0vdspka10
    NOTE: VShell's LSA Module is version-specific, so the LSA Module from a newer version of VShell will not work with an older version of VShell. If you have upgraded VShell to a newer version and subsequently downgraded to an earlier version of VShell, you will need to make sure that an LSA Module from the older version is installed which is compatible with the older version of VShell. For assistance with this process, please contact

B) Verifying the LSA Module is Loaded
Microsoft Windows only loads authentication modules during startup/boot-time, so even when the above two elements have resulted in a verification that VShell's LSA Module has been installed, the machine must be rebooted in order for the LSA module to be loaded and used by the Windows operating system.

To ensure that the LSA Module has been loaded by the Windows operating system, reboot the Windows machine following your VShell installation.

NOTE: VShell's 32-bit LSA Module will not be loaded by a 64-bit version of Windows. Newer versions of 32-bit VShell will not permit installation on a 64-bit version of Windows. Older versions of VShell that were only available in 32-bit installations (all VShell versions prior to 3.0) will only be able to perform public-key only authentication on a 32-bit version of Windows.
Jake Devenport
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Last edited by jdev; 04-23-2019 at 12:02 PM. Reason: Change icon