In order to fix the issue, I suggest you uninstall the utility and then install it again. If the password is still not working, access Control Panel > Appearance > Folder Options, click the View tab, check the Show hidden files, folders, and drives box and click OK. In the Search programs and files field from the Start menu type
win_mpwd_sys.dat and delete all the displayed files in order to be able to open the files locked with Folder Lock. After that, remove the program from your computer, run CCleaner and download and install the latest version of the software. If you still have problems, you need to contact the developers.