To anyone who decides to help: I thank you 500 times. ^-^
 
My Dell notebook PC has had this problem for a long while now; by now, I can't even remember when it started. It's still as frustrating as ever, though. At some point, my PC's built-in Bluetooth started malfunctioning. Most of the time, it would randomly stop working, making it hard to connect any bluetooth devices during those short moments when it did work (though once anything was connected, it would keep working until I disconnected it). I eventually tried uninstalling, then reinstalling my bluetooth stack; that didn't help. Suddenly my bluetooth wouldn't work at all, and the bluetooth icon in the system task tray was always red. I now had a whole batch of new problems that still haven't yet gone away:
 
The USB logo constantly pops up, saying (in a speech bubble):
 
"USB Device Not Recognized
 
One of the USB devices attached to this computer has malfunctioned, and Windows does not recognize it. For assistance in solving this problem, click this message."
 
Almost every time the speech bubble pops up, it's accompanied by the sound effect of a USB device being plugged in, then immediately by the one for the same device being removed.
 
The bluetooth logo has disappeared from the Control Panel's network settings, and I can't access the bluetooth controls by any other means, either. My PC's bluetooth LED indicator is always on, even when in sleep mode (it only turns off if the PC is shut down, or is in sleep mode with the power adapter unplugged). I'm likely forgetting something even now.
 
After these problems started, I uninstalled the bluetooth stack; it wouldn't work anyway, and I'd had an idea (which didn't end up working). By now, out of desperation, I've downloaded updated bluetooth drivers & stacks from Microsoft, Broadcom, and Dell, and tried installing them one by one; nothing worked, and I often get a pop-up error window saying that no bluetooth device was detected.
 
As I said, any help would be greatly appreciated.