Hi,I am unable to connect to Vista machine from XP system through remote desktop. The error is " The remote computer require Network Level Authenetication, which your computer does not support." If try from another vista machine, i can type the login and password; but it shows a blank srceen with "Access Denied" message. If any one knows the solution. Please help..Sajesh

Hi Sajesh, Thank you for your posts. I know that connecting to the Windows XP computer from the Windows Vista computer failed. If the connection works before, we can also restore the system back to the previous status when the issue didnt occur with System Restore. (Note: Performing a system restore may cause the loss of the current system settings; therefore, before doing this, please make sure that the system restore point is not too old and set a restore point for the current status.) Based on my research, I would like to suggest the following: 1. Ensure the Remote Desktop Connection (Terminal Services Client) on both of the computers are up-to-date Description of the Remote Desktop Connection 6.1 client update for Terminal Services http://support.microsoft.com/kb/951616 2. Turn off Network Level Authentication on the Windows Vista side: 1) Click Start, right-click on Computer and select Properties. 2) Go to Advanced System Settings 3) In the System Properties window, please go to Remote tab and select "Allow connections from computer running any version of Remote Desktop (less secure). 4) Please check if it works. 3. Adjust the Authentication Level on the Windows XP side: 1) Click Start, click Run, type regedit, and then click OK. 2) Use one of the following methods: To modify the registry settings for all the users who log on to the computer, locate and then click the following registry subkey: HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Terminal Server Client To modify the registry settings for only the currently logged on user, locate and then click the following registry subkey: HKEY_CURRENT_USER\Software\Microsoft\Terminal Server Client 3) On the Edit menu, point to New, and then click DWORD Value. 4) In the New Value #1 box, type AuthenticationLevelOverride, and then press ENTER. 5) Right-click AuthenticationLevelOverride, and then click Modify. 6) In the Value data box, type the value 0, and then click OK. For more information, please also refer to the following document: Vista Remote Desktop Connection Authentication FAQ: http://blogs.msdn.com/ts/archive/2007/01/22/vista-remote-desktop-connection-authentication-faq.aspx Thanks. Nicholas Li - MSFT Nicholas Li - MSFT

Enable Allow connections from computer running any version of Remote Desktop option in Windows Vista should solve your problem. You can also take a quick look on this Remote Desktop configuration in Windows Vista article. Hope it helps..

By default, Network Level Authentication is disabled in Windows XP Service Pack 3. To enable Network Level Authentication, you have to turn on the Credential Security Service Provider (CredSSP). For more information about how to turn on CredSSP read this article...http://support.microsoft.com/default.aspx/kb/951608If your still running XP SP2 you can download and install a RDP 6.1 client that supports NLA.http://support.microsoft.com/?kbid=952155There is NO NEED to disable NLA login on your Vista host. FWIW here is my small Remote Desktop help page...http://theillustratednetwork.mvps.org/RemoteDesktop/RDP6ConfigRecommendations.html MS-MVP Windows Desktop Experience, "When all else fails, read the instructions"