My wifi connection is gone, but I got ethernet. Could it be the wireless adapter, I had the similar problem with the erased windows 7, but the wireless usb adapter what I used doesn't work for Ubuntu. I got Acer Extensa 4420... Any ideas?
simply taking their solution 2 and tweaking it to look like :
If you notice that the wifi speed improved, then make the change permanent :
and add this line to the file:
save and quit.
If you're on battery, turning off power management could help as well