I recently upgraded my copy of Windows 7 Ultimate to Windows 10 Pro and noticed that Bluetooth was now longer available.
No Bluetooth (or unknown) items were listed in Device Manager and installing the Windows 7 Bluetooth drivers (provided by Dell) didn’t help.
Knowing that Dell will probably never release new drivers for such an old laptop (late 2009) I decided to source my drivers from a competitor… Lenovo.
They use the same Broadcom chipset as the Dell Wireless 365 Bluetooth Module.
So, if you have the same problem then simply download and install the drivers from the following link.
http://support.lenovo.com/us/en/downloads/ds031759
My Wi-Fi kept cutting out after the install (when streaming music to my Nokia MD-12), but a quick restart seemed to resolve that.