Fail to remote desktop to Windows 2008 server with error Network Level Authentication Print

To enable NLA in XP machines; first install XP SP3, then edit the registry settings on the XP client machine to allow NLA

• Configure Network Level Authentication

1. Click Start, click Run, type regedit, and then press ENTER.
2. In the navigation pane, locate and then click the following registry subkey: HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Lsa
3. In the details pane, right-click Security Packages, and then click Modify.
4. In the Value data box, type tspkg. Leave any data that is specific to other SSPs, and then click OK.
5. In the navigation pane, locate and then click the following registry subkey: HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\SecurityProviders
6. In the details pane, right-click SecurityProviders, and then click Modify.
7. In the Value data box, type credssp.dll. Leave any data that is specific to other SSPs, and then click OK.
8. Exit Registry Editor.
9. Restart the computer.

Detail: http://vidmar.net/weblog/archive/2007/05/27/The-remote-computer-requires-Network-Level-Authentication-which-your-computer.aspx