I added a new PC to our WORKGROUP and all the other PC's on the network can access the shared folders on PC A, but PC A cannot access any shared folders on any other PC. They all ask for credentials, we don't use credentials, credential manager is disabled on all PC's, all my advanced sharing options are correct. I've started all function discovery services, SSDP, UPnP device host on all PC's and allowed blank passwords in all local security policy. Can anyone help? I've also tried disabling antivirus and firewall on all PC's. All PC's are all up to date with Windows 10 pro updates.