Solved Network Sharing turns ITSELF off!

(W11 Pro 25H2 )
After years of being annoyed with Windows networking between my desktop and my laptop I recently found some deeper setting that got them to consistently see each other and play nice. I can't for the life of me remember the settings now, one of them involved a Reg edit, or something similar I don't think I'd seen before, that removed the need for login to see each other.
Anyway, today I tried to copy a folder I was working on from my laptop over onto my desktop to continue work and each others' network drives were not visible to each other, from shortcuts, or from File Explorer. From either machine.
So I thought I'd look for updates, have just updated both machines to 25H2 latest update.

On the laptop I can see network and file sharing is active, the network is private, ll looks OK, the other devices, NAS drive etc can be seen over the network, but the desktop has issues.

On the desktop machine, when I go to the Network tab in File Explorer I get the message 'Network Discovery and file sharing are turned off. But clicking to turn it on the same message reappears. When I visit Advanced Sharing Settings I can see Network Discovery and File and Printer Sharing are both turned off, but when I turn them on, go back a page and come back, they are off again.

Network Discovery is disabling itself, my Main PC needs to access my NAS drive and my laptop for daily office tasks, any ideas what i can try, to fix it? Thanks!

OK, I solved it! I realised that if I turned off the firewall it came back, so I reset the firewall to default settings! All solved!