@Pol de Lepel I created a guide with 10 screenshots hopefully demonstrating the few easy steps: [HOW-TO] Connect to OMV SMB shares with Windows 10
Client OS was Windows 10 Enterprise with all updates applied but this shouldn't matter that much since the differences between different Win10 versions are just Enterprise fortunately having stopped the horribly stupid idea to allow guest logons (which is not needed anyway, with OMV it's that easy to create and maintain users/passwords that guest logon should be disabled anyway).