It is probably a driver issue. You can try unplugging the camera. Insert the CD/DVD that came with the camera. Select install driver (or whatever your installer package calls them). Once complete, reboot the computer. Then boot up the PC as normal, and login. Then connect the camera and wait a minute or so while the drivers find the camera.
Alternately you can just use a card reader. This is both faster and simpler. Just get a card reader that supports your memory card format (most likely SDXC, but check your camera documentation). Plug in the reader in to a USB port, wait a few minutes and then plug the memory card in to the appropriate slot. The memory card will now be mounted like a hard drive. Click on my computer. Open...