Networking Notworking .. Again

I am really tired of Win 10 networking falling apart.
I have an incredibly simple setup yet for some reason about every six months it just totally fails.
I have three PC's. A B C.
They could all see each other and all transfer files.
I installed Windows 10 Pro on two of them and that caused a problem.
One PC can see all the PC's but the other two can see nothing on the Network. Troubleshooter fails to find any problems.They are all setup the same.

davefaz said:

They are all in the same workgroup, yes. They are all on the "private" network.
I really just don't understand it at all. Even from PC A which can apparently see the other PC's, it can not access any of the PC's and troubleshooting just fails to identify any problem.

There is some good info in this thread. Especially the 2 services mention. Have a look:

Computers can't see each other after upgrade to 1803 Solved - Windows 10 Forums

davefaz said:

Seriously? SERIOUSLY? OMG MICROSOFT!
You are 100% correct, sir, this has solved the problem. I really can't believe it. How dumb is that.
I am indebted to you!
Oh wait, I can see the PC's but I can't access them... let me see if I can sort that...

Give it 2-3 minutes to settle. At first you'll see the PCs in Network, wait a bit for them to sync up.

Also, there some very helpful steps from @Eagle51 in this post. They go a bit further if you need to...

One PC out of 3 Can't See Others on the Network - Page 3 - Windows 10 Forums

davefaz said:

Ah, UPnP Device Host is not running. Do I set that to auto?

I am following the advice in the post you linked to it stated....

*****************
I would check to make sure all services are running that are needed:

DNS Client
Function Discovery Resource Publication
SSDP Discovery
UPnP Device Host

see this thread Turn On or Off Network Discovery in Windows 10 | Windows 10 Tutorials

Check over all of it please to make sure nothing is missed.
***************

Well, UPnP is missing! It is set to manual and is not running. What should I do?

Mine is manual. That's Universal Plug and Play. Leave it. If still not connecting, look at the steps in the link to Eagle51 post. I did all of those, including disabling IPV6, and mine has been behaving.


After getting all the pieces in place, and rebooting all machines, you need to let it settle and sync up the network. Won't be instantaneous.