Failed to connect to server. java.net.ConnectException: Connection timed out: no further information. Version 1.8.9

After "upgrading" to the Microsoft Minecraft launcher, neither my son nor I can play a multiplayer game. Both of us now receive the error "Failed to connect to server. java.net.ConnectException: Connection timed out" after a two minute delay.

Steps to reproduce:

My son and I both migrated our account to "Microsoft-Mojang" accounts (that uses an e-mail address instead of a username). My environment is shown below. I am trying to play a multiplayer game using Minecraft version 1.8.9.

1. Start the Microsoft version of the Minecraft launcher, select Minecraft version 1.8.9 (see "lan game error 1" attachment). Click Play.

2. Click "Multiplayer" and select the LAN game you wish to join (LAN game has already been started and it is version 1.8.9). Click Join Server.

3. After about 2 minutes, you will receive the error message "Failed to connect to server. java.net.ConnectException: Connection timed out: no further information"

What I expected to happen:

At step 3, I expected to join the LAN game already in progress.

When did this start happening:

As soon as my son and I migrated our accounts to "Microsoft-Mojang accounts."

We NEVER had this issue with our original Mojang accounts (that used a username instead of an e-mail account).

Now that we have migrated to Microsoft-Mojang accounts, nothing works!

Environment:
Minecraft 1.8.9 (1.8.9/vanilla)
Windows 10
Java 1.8.0_25 64 bit
CPU: 8x Intel(R) Core(TM) i7-4770 CPU @ 3.40Ghz
Display: 1920x1017 (ATI Technologies Inc.) AMD Radeon R9 200 Series
Profile Context: 21.19.137.514