Many thanks to SWLing Post contributor, Paul Evans, who notes:
Users of these two propagation prediction programs will find that they don’t work beyond Dec 2019 because the SSN look-up files didn’t go any further.
I noticed this 2-3 years ago and added to the end of the files required. I entered guesses for solar activity values, but with auto mode turned on they will fetch current values. At least this will get you started again. Or my guesses might be right!! 🙂
For Ham CAP use: http://w4.vp9kf.com/SSN.dat
For VOAProp use: http://w4.vp9kf.com/ssndata.txt
Download them and swap them into the directory where the application is located.
Thanks or the help, Paul!