Walkman displayed 'access' now will not switch on

Walkman displayed 'access' after being charged. Nothing would move this from the window and non of the buttons would work, so I pressed reset. Now the device will not switch on. Whn placed in a computer, only once have I managed to get the computer to recognise it as a drive. I formatted it as I was prompted, but then the format failed and the computer failed to recognise the device. Please help!