No files show up on PC

[AC Question]

I am trying to offload my pictures from my Android onto my computer in order to free up some space on my phone. However, when I plug it into the computer (I have tried 3 different ones) and open up the phone, it pops up that the folder is empty. I cannot get to any files or apps on my phone from my PC. Any ideas? It seems to be something with the phone since none of the computers have recognized any files...
Thanks in advance!