Developers use SignetSure to sign files and authenticate those files. You create a digital signature at development time. Your application authenticates the file while running on your customer´s computer. Consider the following two scenarios. Scenario One: You push-publish programs and data over the Internet. Disaster would strike if hackers could impersonate you and send their own files to your subscribers. You have installed a program on the subscriber's machine that receives your files. This program must be able to authenticate files even against a hacker who has reverse-engineered your program. Scenario Two: You distribute registered software with a datafile that identifies the registered user (e.g. user name, product serial number, et cetera). It is important that users not be able to modify their own registration information, even if someone reverse-engineers your program. SignetSure solves the problems of both these scenarios. SignetSure uses RSA public key cryptography. First create an encryption key and sign a file using a simple GUI application. Then authenticate that file with a single API call to SignetSure´s runtime library.