Pictures wont load onto a memory card

Ipluged my LG phone into my computer the other day and started downloading picutres on to it succucsfuly..untill one of the pictures decided to take its time and "prepair" to go into my phone file. It has now been 4 days and the picture is still "prepairing". ive tred to cancel the action and its still loading. the 'x' button at the top of the box is un clickable.ive also tried to see if the problem was just because theres no longer a phone conected to the computer,so i drug a photo from an album onto my desktop and now it "prepairing to put on desktop". somthing seems fishy.