I never had this issue with my D1 or D2g, but with my DX I'm having issues.
My home PC has win7 and Vista both 64 bit machines. I can see everything on my SD card on all pcs at home.
At work we are running XP pro 64bit and I can not see my card when set to USB Mass storage which is what I use at home.
When I select PC MODE, it will bring up the card, but I can only see so much of the card?? I really don't get it.
I do have all the latest drivers, etc.. on the work machine.
One thing to note, I was having all kinds of issues with my DX and someone told me to format my card since I brought it over from my D1. I did do this and only brought a few folders back, music, ringtones, drocap, easymoney, wallpapers and TBU.
My DX has ran so much better, but I have noticed while lookinig at what I can see on my card I'm looking into my drocap folder and I can only see screen shots of the ones that I have taken just recently. I can double click on the ones that are not showing up (thumbnail) and they will pop up in win/fax viewer. This is on my work computer. I have not issues at home