Hi there,
I noticed one of my HP-41 cases had some mildew inside or at lease some black particles that had also filled the yellow foam on the bottom of the inside of the case as well. I cleaned the inside with some isopropyl alcohol and there were tons of particles that came out to the cloth I was using. Is that an OK way to clean the inside of the case? Can I use the case or should I use any other cleaner first? Any ideas?
Thanks,
Andreas

The problem you describe is very common. It seems to be due to the disintegration of the foam rubber layer between the inside liner and outside of the case. Many (myself included) have reported success with turning the case inside out and tossing it in the washing machine with a load of laundry (probably not a hot water load), then let it air dry. Of course, your results may vary, so try at your own risk.

I noticed that the removable foam had mildew in it. I assume then that the foam insulation of the whole case (which I didn't know existed) will have mildew too. Is there any way to remove it if I reverse the case (hopefully without tearing it off)? Can you think of anything to cover it after?

Just unzip it and toss the thing into the washing machine. Then prop open the opening and let air dry. It will come out looking and smelling like new.

This is cool.

I have two 71B cases with the identical symptoms. Thanks for the tip!

Regards,
Howard.

Someone sold me an HP-48G case that is very sticky outside. Could that be from the washing machine by any chance?