Why can't I transfer files from the camera to my computer?

Using a standard usb cable could be the answer. Apart from the charging wires there are other wires (data) that may be wired differently with your particular device than the standard usb wiring. If you got the camera without it's original cable, try to source it's dedicated cable. Else, dig around by surfing the Web to determine the wiring layout of both ends of the cable, then (if you are skilled at fine wire soldering), duplicate a standard usb to usb cable. You don't have to solder the plugs themselves, just open the cable and with an ohm meter determine which plug ends go to which contacts then connect the opened wires in the same configuration - which is somewhat difficult - but can be done with needle pointed probes.