'Local Area Connection doesn't have a valid IP configuration' error message in Windows 7/8 and network not working

Sometimes Windows 7 or Windows 8 network connections seem to have simply stopped working and the following error message appears:

"Local Area Connection doesn't have a valid IP configuration"

To solve this:

1. open command prompt (cmd.exe) as administrator
2. run these two commands:
   ipconfig /release
   ipconfig /renew
3. restart your router
4. restart your computer
5. your network connections should be working again.

Hope this helped you, too :)

Windows networking at amazon.co.uk.