The Register Terminal Services Manager dialog accepts a license key and the name the license is issued to. Once entered correctly, the dialog closes and the program runs as registered from that point on.

Choose Help > Enter registration code.... The dialog also opens when you click Enter license key in the unregistered-version reminder or the support-renewal prompt.
LK1-TSM- and are followed by a long string of characters.Both fields have a small icon on the left (user / key) and accept paste. Right-click for the standard text menu.
After a successful registration the Help > About... dialog shows the licensee name and the license type; the evaluation and support-renewal reminders stop appearing.
If the key is malformed, expired, or does not match the name, the dialog stays open and the next attempt is rejected. Common reasons:
TSM segment).By default the license is stored under the Windows user who entered it; other users on the same machine do not see it. If the program was installed in system-wide mode (run with the /systemwideconfig switch), the license is shared across all users on the machine. Reinstalling or upgrading Terminal Services Manager preserves the stored license; uninstalling without removing application data also preserves it.