I have had my HP 41CX for over 30 years. I have not used it for 25 years since I graduated from engineering. I have multiple application pacs I would like to use. One specifically is real estate pac for finance and TVM calculations. I go to execute by pressing XEQ $ (A) key, and it says nonexistent. Is it possible for these modules to get erased over time? Or become demagnetized? I thought they were hard coded into the chips.
Or
Maybe I am not doing something right to initialize the pacs to enable the overlay?
Appreciate any words of advice.
Thank you, Jim