Try a "Repair" of the program. If that doesn't work, then try uninstalling and reinstalling the program.
To "Repair", click on Start > (settings) > Control Panel > Add or Remove programs, then scroll down to the Serif MediaPlus entry and click it once, then click on the Change/Remove button, click on the "Repair" dot, then click on the Next button.
Jim B. :> )
When all is said and done, usually more has been said than done.