Thanks, I don't think Win 10 uses homegroups or workgroups anymore - that used to work fine!
All the existing (old) computers talk to each other nicely with no complicated share permissions or credentials setup - all computers including the new one just have "Everyone" in sharing permissions with full control/read/changes.
It is just the new one that can see some and can't be seen by the existing ones or needs credential login
I also set up Guest under credentials for all but made no difference. I haven't had to do that previously for any.
You said "The way to get what you are asking is to enable Guest access" - please could you elaborate where to do this in case I have missed this somewhere
Some can see drive c of the new computer but need credentials to go further
Some cannot see it or be seen by it
I am not worried about moving between network - our system is purely in house so full access to everything without any logins anywhere is what we want.
Very frustrating!
All help appreciated!