LogonAsUser( $Domain, $User, $Password [, $LogonType ] )

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Any script that uses this function requires the following privileges (you can set these in the User Manager):

Privilege
      Description

SeTcbPrivilege
      Act as part of the operating system.

SeChangeNotify
      Bypass traverse checking. This privilege is needed only if the acount the script runs under is neither the local system nor a member of the Administrators group.

SeAssignPrimaryToken
      Replace a process level token.