If you have allowed desktop access from "My Computer" --> Properties --> Remote tab, you may want to check if you local policy is set correctly.
To resolve this issue, add allowed users to the Remote Desktop Users list:
1. Click Start, point to Settings, and then click Control Panel.
2. Double-click System, and then on the Remote tab, click Select Remote Users.
3. Click Add type in the user account name, and then click OK.
If you are adding more than one user name, use a semicolon to separate the names.
Note: Adding users to the Remote Desktop Group requires that you are logged on through an administrator account.
Also, make sure that the Remote Desktop Users group has sufficient permissions to log on through Terminal Services. To do this, follow these steps:
1. Click Start, click Run, type secpol.msc, and then click OK.
2. Expand Local Policies, and then click User Rights Assignment.
3. In the right pane, double-click Allow logon through Terminal Services. Make sure that the Remote Desktop Users group is listed.
4. Click OK.
5. In the right pane, double-click Deny logon through Terminal Services. Make sure that the Remote Desktop Users group is not listed, and then click OK.
6. Close the Local Security Settings snap-in.
