I am reaching out to see if anybody might have some suggestions for me, for which I would be extremely grateful. About a week ago at home and at my cottage 4 of my Windows 10 Pro computers were infected on the same day. I have no idea by what ransomeware, or how it got into my two networks, or why it only infected 4 (3 PCs and a laptop) of my 8 PC's. Each of these machines was protected by both Malwarebytes Pro (running real time) and Norton Security. As soon as I discovered this I disconnected them from the network, ran both security software scans and then visually checked my data files. Neither security program detected any malware. Almost all files now had a new ..readme extension and I found the ransom note (I will try to attach a photo of that screen.) Over the next few days, I then reformatted each of the boot drives and all of the data disks. I then reinstalled Windows 10 and applications. Unfortunately, I did not think to save file copies of the ransom note or any of the encrypted files.
My problem now, which I have spent days trying to solve, is that none of the x-infected computers will show up on the network via File Explorer. They cannot see themselves, or any other PC's. I can however ping them and see them on network scans and use the browsers to the internet. Even doing a cmd net view does not work (get various error messages) or doing a full Windows network troubleshoot, or doing a Windows networking reset on them, or doing a cmd reset on them has worked. I have also done a full reset on my routers. All other devices can be seen in File Explorer (Network) as before.