This problem popped up in one of my customer's Win 7 PC last month after an Avast update that never completed and the PC would not shut down. I tried safe mode, disabling shields with no success. Oddly, though it would hang on Removing temporary files after trying several system restore points, it would be fine after a forced reboot, and then back to the same no-internet condition with the next restart of Windows.
Avast 2014.9.0.2021 would not let me fully stop it from loading under the registry Run list, Admin Services, msconfig start, or Task manager. It was protecting itself much like a virus.
Finally decided to uninstall it which gives no indication of its active progress. Discovered that it was trying to install an emergency update which was suspending the uninstall

. Once I killed off the emergency update which was hung anyway, the rest of the uninstall proceeded snappily.
Rebooted after the uninstall, checked that Avast was no longer active, and found the Internet services via wifi and ethernet cable were restored. Even though still had about 8 months to go on the Avast subscription, it's not worth the problem it caused.
Installed Avira, which has less system drag, better reputation for staying out of trouble, and also comes in free and subscription styles.