Hi, Jorge;
you can try resetting the calculator:
press [ON] and hold it;
press [C] and release it;
release [ON].
The calcualtor resets to a known condition. It is not supposed to clear memory contents. If it does not work, a hardware reset is available by carefuly removing (and placing in a safe place) the upper-right rubber feet, facing the back of the calculator, and gently inserting the tip of an unfolded paper clip in the small hole you'll find in the rubber-feet recess. As you feel the paper clip tip cannot go any further, it means you succeeded closing the reset contact in the mainboard. Hold the paper clip for a few seconds (three?), remove it and turn the calculator on again. If you still see the message, chances are you have some library installed in the calculator that is searching for some resource in a card. If yours is an HP48G (and not a GX), I see no way to originate this sort of message from an actual invalid data card, only from a program or library.
If neither of the procedures below succeed, I`d suggest trying a memory clear procedure:
press simultaneously [ON], [A] and [F];
release each of them in the opposed order;
you'll see the message:
______________________
| CLEAR ALL MEMORY? |
| |
| |
|YES______________NO |
if you decide for [NO], all memory is cleared.
If you want to keep current data and do not want to clear all memory contents, then wait for some other suggestions. I`d actualy like to know what else to do, too! q8^)
Success!
Luiz (Brazil)