how do i import my photos onto my pc from my ipad

how do i import my photos onto my pc from my ipad, my screen keeps saying my device (my ipad) is unreachable. I am connected using an apple ipad cable to my PC . It will load a few photos and then I get this error message and then I have to restart my ipad to start the process all over again. I am trying to access the internal storage on my ipad and transfer the photo and movie files onto my PC when I get this error message.