Can't find the DNS Servers

[Gary Roach]

Hi all.
I have been trying for several day to get firefox to work on a newly 
installed Debian Stretch system. It Seems that Firefox can't find a DNS 
server. I am having the same problem with apt-get update. None of my 
mirrors can be reached. Ping works just fine. I can't even reach the 
other computers on my home network if I use their names. IP addresses 
work OK. I have installed resolvconf and followed several installation 
instructions to no avail. The name servers for my router 
(192.168.1.1)and both google servers at 8.8.8.8 and 8.8.4.4. are listed 
in the correct file (can't remember which one). This system worked fine 
when first installed. I installed qemu-kvm on the system and I think in 
broke things.I've run out of ideas.

Please help

Gary R.