Replacing an MUI file to get rid of "Default User" on login screen

[KevinB]

Hi all,

 

On the back of this thread I have created a replacement C:\Windows\System32\en-US\credprovhosts.dll.mui file that I want to distribute across the network so that instead of "Other User" the logon screen displays "Enter username and password". Trouble is... I cant seem to come up with a method of distributing it because only the TrustedInstaller local account has any rights beyond RX on the file on workstations.

 

I've tried:

 

• Using a File entry in Group Policy: Computer Configuration/Preferences/Windows Settings/Files to
  
  • Delete and create the file - no effect
    
  • Update the file - no effect
    
  • Replace the file - no effect
    

   

  [*]Using a startup script to

  • copy the file from a network location (that "Everyone" has RX to) - file isn't copied
    
  • delete and then copy as above - file isn't deleted, then isn't copied
    
  • take ownership with takeown and then copy as above - takeown doesn't take ownership for localsystem (as a startup script executes in the localsystem context, that SID should then own the file, it doesn't, it stays with TrustedInstaller)
    
  • use icacls to add SYSTEM:F to the file - permissions are not added because localsystem doesn't have any rights beyond RX and isn't the owner because takeown failed
    

   

 

I'm about to bash the keyboard with my head. Any other ideas out there that will allow me to replace this single file that seems so irreplaceable?

 

Cheers for any clues

Kevin.

[KevinB]

Hi all,

 

On the back of this thread I have created a replacement C:\Windows\System32\en-US\credprovhosts.dll.mui file that I want to distribute across the network so that instead of "Other User" the logon screen displays "Enter username and password". Trouble is... I cant seem to come up with a method of distributing it because only the TrustedInstaller local account has any rights beyond RX on the file on workstations.

 

I've tried:

 

• Using a File entry in Group Policy: Computer Configuration/Preferences/Windows Settings/Files to
  
  • Delete and create the file - no effect
    
  • Update the file - no effect
    
  • Replace the file - no effect
    

   

  [*]Using a startup script to

  • copy the file from a network location (that "Everyone" has RX to) - file isn't copied
    
  • delete and then copy as above - file isn't deleted, then isn't copied
    
  • take ownership with takeown and then copy as above - takeown doesn't take ownership for localsystem (as a startup script executes in the localsystem context, that SID should then own the file, it doesn't, it stays with TrustedInstaller)
    
  • use icacls to add SYSTEM:F to the file - permissions are not added because localsystem doesn't have any rights beyond RX and isn't the owner because takeown failed
    

   

 

I'm about to bash the keyboard with my head. Any other ideas out there that will allow me to replace this single file that seems so irreplaceable?

 

Cheers for any clues

Kevin.

[mrwoberts]

I think it comes down to - who owns the file, and who you are running the scripts as in order to change the owner.

Looking back at that thread you listed, tsears says the following (post #42)

 

I had to have a GPO which changed the permissions on the DLL file and then another one to overwrite the file in question.

 

Is that worth a try?

 

First change the owner to the administistrators group... then a second command [chained] to overwrite it.

[KevinB]

Yep, ownership and permissions was definitely the issue. I was trying all ways to change the permission on the file except via GP as I hadn't realised that was an option. I've found the setting thanks to this useful post: https://mcpmag.com/articles/2008/10/13/file-permissions-thru-group-policy.aspx and used a startup scrupt to copy the MUI file over and hey presto! All is well

 

Thanks for the pointer.

 

Cheers,

Kevin.

[mrwoberts]

Thanks for a link to that article. I've didn't know that either.