I have a HP Pavilion dv6 laptop. The last thing I did before this wireless problem was bring my laptop to school and used it until it ran out of battery. I don't think that should cause any problem.
I went home, plugged in charger, turned it on, and wifi's not there.
The wifi button light was orange and stayed orange. Restarted laptop (a few times).
For once, the light turned blue/orange as I pressed wifi button, but the wifi still isn't there (no access to any connections whatsoever. I don't even see the bars with red X. I just see a plug+monitor with red X).
I got desperate and did a full system recovery (nothing that really needed back up). Wifi worked, but only for a while.
Had to restart (a few times) to get it to work again. Google'd about this and found out about device manager.
Once, when I had device manager up and wifi stopped working, I noticed that the wifi adapter in the list would disappear as well.
Now, the wifi works, but it would sometime turn off for no reason and I would have to restart again.