If you’ve moved your RDCMan RDP files then, it could be that you get an error when you open it telling you it has a problem decrypting the credentials.
Pretty sure this only happens when you move/copy your .rdg file to another computer.
The easiest way around it is just to replace the credentials that are missing.
In my example above it shows it’s unable to decrypt the creds in two profiles.
The easiest way to fix this is to go to the profile settings and enter your credentials in the profile again.