When we sell your products to home users, we would like a simpler way for us and them to enter the username and password information on registration, or most often renewal. I noticed that SlySoft's AnyDVD product has a clever way of doing this; it registers a file handler for extensions that end with .anydvd. If a file named license.anydvd is opened, AnyDVD is invoked, and it would know how to extract the license information and give feedback to the user whether it was updated or not. By keeping this as a simple text file, any reseller could make and distribute such files, and NOD32 would register a file handler for .nod32 or similar. Double-clicking that license.nod32 file would enter/update the registration information.