Issue with PowerShell Remote Endpoints after a Windows 10 Upgrade

  • Context:

I’ve tested recently an upgrade to the latest branch 1803 (aka Spring Creators Update / RS4) of a Windows 10 Enterprise x64 that had a custom remote endpoint configuration.

  • Issue:

Everything was still there. It was still registered, its ACL still set… except that it doesn’t work.
If you attempt to create a new PSSession or use Enter-PSSession or Invoke-Command, it failed with the same error message:

New-PSSession : [localhost] Connecting to remote server localhost failed with the following error message : The WS-Management service cannot process the operation. An attempt to create a virtual account failed. Ensure that WinRM service is running as Local System and that it has TCB privilege enabled. For more information, see the about_Remote_Troubleshooting Help topic.

TCB means Trusted Computing Base. The WinRM service seems to have lost its (SeTcbPrivilege) ability to Act as part of the operating system and cannot create the virtual account used by the remote endpoint.

If I check the services on a 1709, I’ve:

If I check the services on a 1709 upgraded to a 1803, I’ve:

  • Solution 1:

Unregister and register

  • Solution 2:

There are two ways to restore the TCB privilege: either using sc.exe or by setting the RequiredPrivileges REG_MULTI_SZ value in the registry.

# using sc.exe to restore privilege
sc.exe privs WinRM SeAssignPrimaryTokenPrivilege/SeAuditPrivilege/SeChangeNotifyPrivilege/SeCreateGlobalPrivilege/SeImpersonatePrivilege/SeTcbPrivilege
# or directly setting the value in the registry
$HT = @{
 Path = 'HKLM:\SYSTEM\CurrentControlSet\Services\WinRM'
 Name = 'RequiredPrivileges'
 Value = @(
  'SeAssignPrimaryTokenPrivilege',
  'SeAuditPrivilege',
  'SeChangeNotifyPrivilege',
  'SeCreateGlobalPrivilege',
  'SeImpersonatePrivilege',
  'SeTcbPrivilege'
 )
}
Set-ItemProperty -Type MultiString @HT -Force

# Restore the local system account
Get-CimInstance -ClassName Win32_Service -Filter "Name='WinRM'"| 
Invoke-CimMethod -MethodName Change -Arguments @{StartName='LocalSystem'}

# Apply changes
Restart-Service -Name WinRM
  • Misc.:

Can you notice any other difference left by the upgrade?

The DisplayName was changed and the ServiceType was changed from 0x10 (it has its own process) to 0x20 (it’s a shared process).
Don’t ask me why the upgrade changed these settings? 🙄 I have no idea.

Bonus: Solution 1 is better than solution 2 because it also fixes the service type.

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Detect and correct orphaned ‘adminCount=1’ in Active Directory

I recently needed to detect and correct orphaned ‘adminCount=1’ in Active Directory.
I googled that old problem and found the following code: https://gist.github.com/webash/b34c5a422288827ff4e53318e34c6923

I loved his honesty and the fact that he respected the best practice of adding a note where he has acquired the code.
The help also references a blog post on technet.

I don’t like to reinvent the wheel and I couldn’t resist fixing the code anyway.