I have a new Acer Aspire V3-571 laptop with Windows 7 x64. Yesterday I bought a GPS receiver (Qstarz 818XT). It has a wireless Bluetooth adapter just like a keyboard/mouse adapter. I noticed that my laptop was having issues shutting down. I would tell it to shut down, and a few hours later the laptop would still be busy shutting down. I manually shut it down, and when I started it again there was a notification that a crash dump had been created. It also had issues starting up. I found that these problems stopped as soon as I removed the Bluetooth USB receiver from the USB port. I checked the event logs, and they show numerous errors related to the bluetooth device. Always two identical warnings followed by an error. The warning is: Event 3, BTHUSB - A command sent to the adapter has timed out. The adapter did not respond. The error is: Event 17, BTHUSB - The local Bluetooth adapter has failed in an undetermined manner and will not be used. The driver has been unloaded. If I go to devices and printers, this is the information that it shows regarding the Bluetooth USB reciever. broadcom 2046 bluetooth 2.1 usb uhe dongle Device Type: Bluetooth Radios Manufacturer: Broadcom Location: Location 0 (Port_#0003.Hub_#0002) Driver Version: 220.127.116.1100 (Date - 3/16/2012) Also if I check device manager, In Broadcom 2046 Bluetooth 2.1 USB UHE Dongle Properties, I will get a message sometimes saying 'Windows has stopped this device because it has reported problems. (Code 43). After a minute or so it will change and say 'This device is working properly.' Almost immediately afterwards it will change again and display the error message again. Also it shows the yellow triangle by the device, and this disappears when it is 'working', only to appear a few minutes later again.