The D5200 needs to match a Data Lock code in the panel to access programming. Changing the panel Data Lock Code from the default of 12345 will prevent access.
Remote Programming Software:
RPS also needs to match the Data Lock code in the panel to access programming. Changing the panel Data Lock Code from the default of 12345 will prevent access.
RPS also needs to match the RPS Passcode (or RAM Passcode in legacy types) in order to allow access programming. Changing the default from 999999 will block RPS access.