My compact flash suddenly lost 90% of memory.

I have a Transcend CompactFlash 1 GB card that I've used for about nine months, taking perhaps a total of 300 photos with it. Suddenly I find it's only about a 0.1 GB card. There's nothing wrong with my camera (Sony DSC-F828), because my microdrive works fine. Yes, I've made sure the card is wiped clean. I've tried reformatting it, but apparently that's not possible since the Sony menu doesn't come up. Anybody have any idea what's going on here?

did you try reformatting it in the card reader(format f drive?) that may do it?

OTHERWISE you may have a bad sector and need to SEND IT BACK

Alzheimers?

Sorry, couldn't resist that one :)