“ Originally Posted by PsyChoTk 
”
the sw.unl file is the serial number for your card. if you delete it, you have to generate another one and drop it into the garmin folder. also there is a map id .txt file. my map id is 425. i can't say if it will help but drop the attached txt in the garmin folder and let me know if it works.
I can't edit my post so could a mod hook me up.
make sure you have a map .unl file as well check this thread for instructions i posted just before/ and after this one
Code
https://www.wckediden.com/garmin-city-navigator-t187291p4.html