Remote Desktop to Vista Home Premium PCs

In my research for this question it looks like everything has to do with the Network Service Account suddenly not having enough permissions to access the network or becoming corrupt in someway.

Maybe you can try This link which will reset your VISTA security settings.

You can also try restoring an old registry copy if you have one, you would need to boot into the recovery console to replace the files in c:\windows\system32\config

Using Group Policies (best practice) Open Group Policy.

In Computer Configuration, Administrative Templates, Windows Components, Terminal Services, Sessions, enable the settings you want to configure. See the policy explain text for more information.

Or

Using Terminal Services Configuration Open Terminal Services Configuration.

In the console tree, click Connections.

In the details pane, right-click the connection for which you want to modify time-out settings, and then click Properties.

On the Sessions tab, above End a disconnected session, select the Override user settings check box. This allows you to configure time-out settings for the connection.

Configure the following time-out settings as appropriate:

In End a disconnected session, select the maximum amount of time that a disconnected session remains on the server. When the time limit is reached, the disconnected session ends. When a session ends, it is permanently deleted from the server. Select Never to allow disconnected sessions to remain on the server indefinitely.

In Active session limit, select the maximum amount of time that a user's session can remain active on the server. When the time limit is reached, either the user is disconnected from the session or the session ends. When a session ends, it is permanently deleted from the server. Select Never to allow the session to continue indefinitely.

In Idle session limit, select the maximum amount of time that an idle session (a session without client activity) remains on the server. When the time limit is reached, either the user is disconnected from the session or the session ends. When a session ends, it is permanently deleted from the server. Select Never to allow idle sessions to remain on the server indefinitely.

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