Canon rebel xt displaying busy?

I have been having this problem for a couple of weeks now. I can take pictures like I always did without any problems but when I try to put them on my computer the display on my camera shows busy and wont do anything so I thought it was my computer took the camera to radio shack and he tried it on his computer and as soon as he plugged it in the display went right back to busy...does anyone know how I can fix this I have tried everything