Did you use the uninstall util for NAV?
If not:

  • remove Avast
  • use the uninstall util to completely remove NAV
  • reboot
  • install Avast
  • reboot

If this doesn’t solve the problem:

  • Change ODBC to XML in avast4.ini

edit: This has been explained in many other threads already. Please use the search option on this board before asking.