In Windows Server 2003/2008, both Authenticated Users and Users are built-in security principals, but they serve fundamentally different purposes:

• Authenticated Users: Includes any security principal that has successfully authenticated to the domain or local machine (domain users, domain computers, and domain service accounts)
• Users: Specifically contains only interactive user accounts (both local and domain users) but excludes service accounts and computer accounts

Consider this folder permission scenario where the difference becomes critical:

icacls "C:\\SharedData" /grant "Authenticated Users:(OI)(CI)(RX)"
icacls "C:\\ApplicationLogs" /grant "Users:(OI)(CI)(M)"

The first command grants read/execute to all authenticated entities (including services), while the second only grants modify rights to interactive users.

The security identifiers (SIDs) reveal the structural difference:

Whoami /all | findstr "S-1-5-11 S-1-5-32-545"  
# S-1-5-11 = Authenticated Users  
# S-1-5-32-545 = Users group

• Use Authenticated Users when:
  • Resources should be accessible to services (SQL, IIS, etc.)
  • You need to encompass computer accounts in domain scenarios
• Use Users when:
  • Restricting access to human users only
  • Implementing least-privilege security models

In Active Directory environments, remember that Authenticated Users includes:

Get-ADGroupMember "Authenticated Users" -Recursive | 
  Where-Object {$_.objectClass -ne "user"}

This PowerShell snippet reveals non-user entities that would inherit permissions when using this group.

In Windows Server 2003/2008 security architecture, these groups serve distinct purposes:

• Authenticated Users: Includes all security principals that have been validated through logon (both domain and local accounts)
• Users: Specifically contains only domain user accounts created in Active Directory

// Example PowerShell to check group membership
Get-ADGroupMember "Authenticated Users" | Measure-Object
Get-ADGroupMember "Domain Users" | Measure-Object

Key differences in folder permission scenarios:

Example NTFS permission entry in icacls:

icacls "C:\SharedData" /grant "Authenticated Users":(OI)(CI)RX
icacls "C:\Department" /grant "Domain Users":(OI)(CI)M

When configuring folder permissions:

• Use Authenticated Users for general read access across infrastructure
• Apply Users group when restricting to human operators only
• Always combine with granular permissions for least-privilege access

Debugging permission conflicts with Process Monitor:

procmon.exe /noconnect /accepteula /backingfile trace.pml
/filter "Operation is CreateFile" /filter "Path contains C:\TargetFolder"