Laptop sees all other Homegroup computers, but is invisible to them

I've got a LAN with 3 hard-wired computers and 2 laptops. 4 of the machines see one another in the Homegroup, as expected. Then, there's the problem child.

Problem computer can SEE and access each of the other 4 machines. However, none of the other 4 can see or access the Problem computer in the Homegroup. (They can all see it under "network", but have no access.)

Problem computer is W7/32, laptop. The other laptop is W10/64. The other 3 are all W7/64.

I've had the Problem laptop leave, reboot, then rejoin the Homegroup. I've run the troubleshooter from each computer. I've rebooted each machine. No change in behavior.

The one possibility is that the Problem laptop access my network via wifi. The other laptop is docked, and uses an Ethernet connection, just like the other 3 computers.

Problem Laptop is the ONLY machine using wifi.

My router/wifi is an Asus RT-AC68U.

The Problem Laptop has the wifi network set as "home network". All machines have device discovery on, network discovery on, etc.

The odd thing is how the Problem Laptop has total access to all shared resources via Homegroup, but no other Homegroup computer can even see the Problem Laptop.

Any ideas on how to resolve this issue?

Thanks,
Ken

A few things to try:
Attach an ethernet wire to the problem machine.
Try the other laptop on wifi.
If the first test works and the second doesn't, it may be the router needs a flashing.
If both tests work it's probably a wifi problem on the laptop.
Drop the firewall in the problem machine.
Do a clean install of the wifi drivers. Make sure all previous drivers are uninstalled. Firmware could be a problem too.
There are progs such as Complete Internet Repair that will reconfigure your connectivity.

This is weird, but I'll go with it.

I'd done MOST of what was on that list (no changes needed). I'd rebooted all devices/computers. The other laptop worked fine w/wifi. I'd turned my firewall/antivirus off (Kaspersky). No changes.

Then, I had to do other chores, etc. The next morning, everything worked.

I'll ascribe the repair to the fact that my laptop saw the inevitability of what would happen since Sevenforum is on the job, and it decided to give in.

Thanks.
Ken