Are you using the original charger supplied with the device? Aftermarket chargers and usb adapters might not have enough output to power the device up, or allow it to charge properly. I only ask because you say that you're using a desktop charger of some kind. Try the original charger if that's the case. I have a usb adapter that occasionally works, but depends on the host device and it's robustness of usb power. But the Nokia original car power cord works every time and is even better quality than my cell phone charger. Hopefully it's not the power jack in your device. Restart it after swapping batteries and see if that helps. Good luck!