Hey guys.

Im using my Dell Inspiron 15R 5537

After updating to Windows 8.1(one of the greatest mistakes i've ever made LOL)

The laptop occasionally cannot detect the existence of my wireless and bluetooth card

By "not detecting', the Bluetooth setting is not available (grey) to me.

and in Device manager, there is only my wired LAN card and no problem hardware is shown.

Even when i turned to install the latest driver for Win 8.1, all installations failed, either they could not detect any bluetooth device in my laptop.

Here's my device manager for my laptop (which the absence of wireless card makes it weird)

Sorry for chinese letter.

May guys help me sort this our which has bothered me a lot with other issues emerged after updating to Win 8.1 :(