Samples, and sequences won't load on random programs

I don't know whats going on, I hope it is a memory card problem. I like to keep many different beats in progress at once, so I have a lot of programs and sequences saved at different phases of completion. One day I started loading some projects, and I discovered some disturbing issues. Samples were missing on many programs, and when I went back to look at them in sample assign It would say the name of the sample I had saved, with a question mark next to it (?sample1). On other ones, sequences turned up blank. Not every project had these problems. The memorycard is a 4 gb sandisc card. I have used it for a long time, I only recently read that the mpc 500 only takes up to 2 gig cards. Does anyone have any experience with this? Do you think it is a problem with the mpc or the memory card? I was thinking the problem could be that it is not an akai card but it seems unlikely. I got another card, a one gig lexar media card,I havent used it yet, so i dont know how well it will work. Thank you I appreciate any wisdom you guys might have





an updated version of this beat was lost, such a bummer

Possibly the memory card, they have a finite number of reads/writes, they don't last forever.

You should be backing everything up to multiple locations, keeping everything on the one card/disk is asking for trouble.

Good point thanks for the tip