Problem resolving local hostnames

Help
1

I can not RDP to machines on my own network, by name, after installing pi-hole. If I remove pi-hole and go back to DHCP on my router, I can again RDP to 'xyz'.

Pi-Hole is my DHCP server.

I know this question has been asked before and the latest answers simply say use pi-hole as my DHCP server. What else do I need to look at or how can I debug?

2

Here are some tools to play with:

3

This issue sounds similar to Cannot ping pihole server. Its hostname "pihole" does not resolve to its static IP address