It was my understanding that the Remote Desktop Protocol in Windows XP was never going to support Network Level Authentication. Well low and behold, with XP Service Pack 3 you can use the CredSSP Security Service Provider to enable it. The only problem is that in Windows XP, CredSSP is turned off by default.
Turn on CredSSP
- Within the Registry Editor, navigate to the HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Lsa subkey.
- Modify the Security Packages value by adding tspkg to the list of packages.
- Navigate to HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\SecurityProviders.
- Modify the SecurityProviders value by adding credssp.dll to the list of providers.
- Restart your computer.