I bought an Envy 17 laptop running Windows 7 Professional x64. Everything worked fine.
My brother showed me Magicka. Decided to buy it. Found I needed a middle button (why don't laptops have middle buttons?). So I bought a Microsoft 5000 Bluetooth mouse. Got it, put in the batteries switched it on, my laptop saw it, downloaded the Intellipoint drivers, I played a bit of Magicka and then exited out and turned the mouse off as I awaited my brothers return from Warsaw. That was the only time the mouse has worked.
Now two weeks later nothing I can do will allow my laptop to see the device. I followed various pages on the Microsoft Knowledge base and nothing worked. I then tried to see if I could see any other devices - I set my HTC Desire to discoverable but my laptop couldn't see that either. The batteries are fine - the battery tester needle flies over to 'max'. Trying to rediscover it doesn't work either.
There are two bluetooth services running (seemingly correctly) but can't see anything. I don't own anything else bluetooth. I am currently sat in my hotel room annoyed that I can't get this working.