Here’s a “duh” for you…
If, when trying to log onto a Win XP machine via Remote Desktop, you get:
"Unable to log you on because of an account restriction."
This can occur if the account you are using to connect with has a null (blank) password.
Apparently you cannot establish Remote Desktop connections when you are using an account with a null (blank) password.
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This can also occur when you have the ForceAutoLogin set in the registry at
HKLM\Software\Microsoft\Windows NT\CurrentVersion\Winlogon
You need to find the corresponding key AllowMultipleTSSessions in the same section of registry and set this to 1 to allow a remote desktop session to log off the autologgedon user.