No network after Windows 10 update 20H2

A customer lost all network connectivity after an automatic Windows 10 update to the 20H2 version. The following symptoms were observed:

  • Event viewer log reported AVG anti-virus was uninstalled due to compatibility problems during the update
  • Loss of connectivity on both wireless and ethernet adapters – unable to get a valid IP address, getting a 169.254.x.x address
  • After assigning a manual IP address, trying to ping any address results in “General failure” message
  • Event viewer system log also shows errors:
    netbt event id 4307 – initialization failed transport refused

Resetting Network & Windows Firewall settings made no difference.

Turning off the Windows Firewall prompted for AVG to be re-enabled, hinting that AVG had not been completely purged from the system.

Using the AVG Clear uninstall program from AVG’s website to complete the uninstall process fixed the network problem!