Summary
By default, the Sessions dialog box maintains a list of all sessions created on the computer. If you move or delete the appropriate session files, when you try to open the session from this list, you will be prompted to remove the session from the list. This list is maintained in the registry. You can edit the registry to directly remove items from the listing in the Sessions dialog box.
The File menu maintains a list of recent opened sessions. You can edit the registry to clear items from this list.
More Information
To remove items from the Sessions dialog box
regedt32
To remove items from the Recent Files list
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