For the past 7 years I have used an O2 mobile dongle to access the internet with little or no problem. Suddenly last night it would not connect, telling me that 'Ethernet 2' does not have a valid IP configuration. I have spent all day shutting down and unplugging/plugging to no avail. The dongle flashes as though it's working but I was still getting the message, 'No Internet'.
Anyway, to cut a long story short I tried one more time and when it didn't work I clicked on restart rather than shut down and lo and behold, here I am again. Can't fathom it.