This will occur if your Program Files folder is set for "administrator privileges only", or "read only". I'm not "exactly" sure how to tell you (depends on windows version), but if you go to your "File Explorer" and right click on the "Program Files" folder and choose PROPERTIES. You will see several options. You need to UNcheck "read only" if it is set for that, AND also under Sharing, you can tell windows to share that folder.
Then, usually you can write/save files that are going to a sub-folder inside "Program Files", such as c:\Program Files\Scancat-Lite-Plus\
when I go to file save it acts like I am doing a search instead of save by coming back and saying file not found, it also says that simple file names like andy.rsd are invalid.