On Windows 7 Home Premium and Windows XP Pro, the IOGEAR Bluetooth 2.1 USB Micro Adapter has never worked under any circumstances. It would at best display a cryptic error code: 0x80004005. Never buy this IOGEAR adapter.
A Bluetooth adapter that worked flawlessly is the Targus USB Bluetooth Adapter. This adapter works beautifully and was easy to install.
Both adapters however only come with a mini-cd disc to install the drivers & software, so download the software from their websites, in the event you don't have a mini-disc drive.