vCenter Single Sign-On “Cannot parse group information” Error

There is an authentication issue with vSphere Single Sign-On version 5.5 when running both the Active Directory (AD) domain control and the vCenter Single Sign-On Server on Windows Server 2012.

when your AD domain controller and your vCenter Single Sign-On are both running on Windows Server 2012, the single sign-on is unable to authenticate AD users.  You get a “Cannot parse group information” error as shown in figure below.



  • Users cannot authenticate with a Vcenter Single Sign-On (SSO) 5.5 system that is installed on Windows Server 2012 when this system is joined to an Active Directory domain controller also running on Windows Server 2012.
  • Users receive this error message when trying to log in through the vSphere Web Client:
    Cannot Parse Group Information

Reason of this problem

  • This issue occurs only in environments where BOTH of these conditions apply:
    • vCenter SSO 5.5 is running on Windows Server 2012, and
    • vCenter SSO 5.5 joined an Active Directory Domain with a Domain Controller that is running on Windows Server 2012


This is a known issue affecting vCenter Server 5.5.

To resolve this issue, replace the %WINDIR%\System32\idm.dll file on all systems running Vcenter SSO 5.5 with a idm.dll file which you can download from

Note: The attached idm.dll file is provided by VMware.

To replace theidm.dll file on the Windows Server 2012 running SSO 5.5:

  1. login as an administrator.
  2. Stop the VMware Identity Management Service on the vCenter SSO server. This also stops the VMware Secure Token Service.
  3. Back up the existing idm.dll by copying %WINDIR%\System32\idm.dll to %WINDIR%\System32\idm.dll.orig.
  4. Download the attachment that contains the replacement idm.dll file and paste it in %WINDIR%\System32\.

Start the VMware Secure Token Service on the vCenter SSO server. After replacing the dll and restarting services, the initial AD login may take longer than normal to authenticate.