My USB ports have been working just fine until recently. All of a sudden, as of not too long ago, USB data transfer no longer works at all. For example, when I plug in an MP3 player, the device will charge as normal. However, Windows will not recognize it, and I have no way of accessing or swapping files on it. The exact same happens for my cell phone. Every port does this, back and front, and these devices work perfectly on other PCs. Strangely, however, is that I have 2 other devices plugged in - an external HD and a mouse - and both work fine. However these both came with driver CDs.

Do you plug the USB devices one by one and only the USB ext hdd and USB mouse work properly ? Or do you plug the non-working USB devices when the ext hdd and USB mouse are plugged ? If the USB devices do not have their own power source, then you may have trouble operating them. Therefore, I suggest that you unplug any USB device when you do not need it or try a powered USB hub. Regards SuatCINI

The external HD has its own power source. The mouse does not. Unplugging the mouse makes no difference unfortunately.

Can you restore Windows to a time when all your devices worked happily together and check if all your devices work properly after restoration ? Regards SuatCINI

Unfortunately I don't have a restore point far back enough.