Windows: Cannot team Broadcom NetXtreme adapters. Please select an adapter with NDIS 6 driver error.

This is most likely caused by software firewall, such as Symantec EndPoint Protection or Vipre Enterprise. Disabling them usually won’t help either. You will have to uninstall the firewall and then attempt to team your adapters. If that didn’t work uninstall both firewall and BASP, install BASP, team and then reinstall your firewall.