Can't see Win10 PC on network after KB4041676 Cumulative Update

Windows 10 installed the KB4041676 cumulative update to 1703 build 15063.674 on my Toshiba notebook last night. Now the 3 other PCs on my home network can't see the Toshiba anymore. But the Toshiba sees them and connects to the Internet via my Netgear router. Systems on the network:

* Desktop running Windows 7 64 bit
* Desktop running Windows 10 32 bit
* Notebook running Windows 7 32 bit
* Notebook running Windows 10 64 bit

Options in Advanced sharing settings 'Private (current profile)' haven't changed:

[x] Turn on network discovery
. . [x} Turn on automatic setup of network connected devices
[x} Turn on file and printer sharing.

Under 'Settings > Update & security >Troubleshoot' I ran the 'Incoming Connections Troubleshooter > What are you trying to do > Share files and folders'. That reported, "Problems found - Windows requires more information to diagnose the problem. - Not fixed." I have yet to get any troubleshooters in Windows to fix these sorts of issues.

I don't use the Homegroup for sharing, preferring to share individual folders on various systems. So I have turned on password protected sharing on each system and have created user accounts on all systems for the same 4 users on all 4 systems.

Any suggestions on what may have caused this, and how to fix it?

Thanks for any thoughts on all this. :)

Edit: Also ran these troubleshooters with no success:
* HomeGroup
* Internet Connections
* Network Adapter

Have also tried disabling antivirus
Disabled the Windows 10 Firewall.
Network properties on Toshiba shows IPv4 & IPv6 connections made in both Wifi & Ethernet individually.
I am able to ping the Toshiba from the other systems.