new sd card messed up camera viewer

[Guest QuickHonda]

I have the camera set to store photos on my memory card and now that i replaced my 2 gig card with a 4 gig card the samsung camera picture viewer won't show any of the old photos, only new ones. I formatted the new card using the phone then copied all the files from the old one onto the new one using an xp machine. The old photos are still there and the camera numbering system isn't overwriting them so it must recognize that they are there but it refuses to show them. Other photo viewers show them all with no problems. help....