Ping by Name fails

[shawnmatlock]

Hello,

I have a Windows 2012 host with VirtualBox 5.2.6 and two Windows 2016 guests.

The guests do not respond to ping by name from outside the host. The response is "Ping request could not find host...." (Ping by IP works.)

Originally, I thought this was a DNS issue (it may still be), but the entries are in the DNS A Record.

A couple of interesting notes:
1. With the Windows Firewall turned off for the guests, they respond to ping by name. (I've opened a ticket with Microsoft, but haven't gotten far with them, yet.)
2. With the Windows Firewall turned on, when I change the guest Network Adapter Promiscuous Mode (from Deny to Allow All, or from Allow All to Deny), the guests respond for a while then stop, again. (This is the reason I've asked in this forum.)

Any thoughts on how to permanently resolve this?

Thank you,
Shawn