Hi everybody,
Recently updated my Aspire S5-391 to Windows 8.1 (pre-installed Win 7 Home Premium x64, and did a clean intall for windows 8.1 from Image). I installed all of the latest drivers and found something wrong with bluetooth connectivity.
Initially I had the same problem as another member of the community who uses S7 and lost bluetooth device in the device manager completely as soon as updated to windows 8.1. However, I did a recovery for windows 8.1 and the bluetooth can be toggled on by pressing FN+F3 after the recovery. Afterwards, I tried to pair my Bluetooth mouse to the computer. The mouse I paired are Dell WM713 and Logitech T630, both of which works well with my Dell XPS 12 win8.1, whose Bluetooth adapter is Intel 7260.
Both of the mouses can be successfully paired, but later issues came. The mice suddenly lose connectivity and stop moving while using (not during idle period). swithcing the mice on and off would not reconnect the mice to the computer. However, this connectivity issue can be immediately resolved as soon as I go to Metro's PC Settings-PC and Devices-Bluetooth. Once the "Bluetooth" configuration page is opened, the mice are reactivated.
I updated the driver of the mice and bluetooth adapter to the latest version and did some clean reinstallations but the issue persists. Besides, I found many other members complaining about bluetooth connectivity problems after upgrading to windows 8.1. All of these acer users have PCs with Atheros WLAN/Bluetooth adapter. I believe this is a recognized problem and I hope Acer can do something with Atheros to resolve this issue ASAP.