Z*.tmp instead of Arial font

This is an old problem. Why hasn't Asobe fixed this error yet?

Every week I'm finding that the Arial font suddenly no longer works. It changes to Z*.tmp and types gibberish instead of Arial. A fix is to reboot windows, go to the acrobat_sbx folder and delete the 100s of Z*.tmp files that have accumulated.

They shouldn't be there. Adobe, this is sloppy. This error has been around for years. These Z*.tmp files should not be staying there and spoiling the program. Could this bug in the program please be fixed?

Many thanks.