I encountered an issue on a system I had deployed where it was unable to connect to the internet or do any DNS resolution post-Deployment.

I found that underneath the TCP/IP properties for both the WiFi and OnBoard ethernet that automatically obtain DNS servers from DHCP was unchecked and the IP of my primary DC was hard coded.  I suspect this was because the specific subnet the system was on can't auth with my PDC however am a bit surprised that it left behind a hard-set TCP/IP entry.