I imagine Node-Red would be inheriting the permission of the service it is running as. Based on the fact that you have not stated these machines are in a Domain i would therefore assume they are standalone servers. I have not looked at the SMB node - are you able to give it permissions ? (i.e. user credentials) for the remote machine ?
Also have you checked that filesharing is enabled on the machine that you wish to create the file on - and also what firewall is in place and if it allows connections.
An easy test of some of this is to go to the command line as an administrator and type
Net use * \\Remote Machine Name\c$ /user:administrator and provide the admin password (for the remote machine) when requested
If this works you then know that
- Filesharing is enabled
- the firewall is allowing SMB packets through on both machines
Craig
