How can I prevent someone from just copying my program from the folder it was installed in and putting it in on another computer, i.e. just copy the installed .exe?
Generally you cannot copy a program exe from one computer and have it work on another. If you have installed components for your application then the other computer would need to have those components on it as well. There is no way to keep someone from coping your program to another computer, the only thing you can do it to make it not easy to get it to work on the other computer. IE. Look for a hidden file and/or registry entry that your installation created and if it is not there then the program would not run.
Just copying the exe will not work on another computer without the vb references in your program installed on the other computer.
Very precise answer as is to be expected from you. I am glad you can share this knowledge with me. And I, too, thought about storing a small file in some other folder so that if it was not present on the computer then the program would shut down.
Thanks for your help all these years. :)