I need to register mscal.osx in order to use ARCOS PC Field Edit. However, when I try to register through command prompt, I get an error saying that it failed to load.
As far as I know, in 2015, the Department of Justice was looking to replace ARCOS PC Field Edit Application with an online version of the service and was dropping support for the PC application. So, it's very likely that the reason you can't register the program is that it's no longer available.
Unfortunately, the only advice that I can give you is to get in contact with the people that made the software available and see if they can help you.
