[Blind-sysadmins] win10 machines not playing nice with each other

Hello, I've got a network with several win10 machines on it. One all can get to and pull shared files. Two others are not sharing, the shares are visible, under thieir computer names, but when I go to them I get an error user is not authorized. Permissions on the shared folders are to allow everyone full access, that's under the sharing tab as well as the security tab of the folders in question. I am not using home groups and all of the machines are in the same workgroup. If I had a Pi I would look at setting up a domain. Any help appreciated. Thanks. Dave.