With Windows Explorer I can browse and edit all the Mac local files (including system files). I created a new Windows user and this was worse - I could not see anything on the Mac. Just to be sure I deleted some shares and re-created them (no difference). I have already been through those links (and more) many times, and the settings were all as they should be. It's not the end of the world to share through the Mac internal drive, but I want to add a bigger USB drive and share it - it does not look as if it would work. The most appropriate seemed to be to turn on some SMB settings, but that did not work. I have searched through multiple Windows side suggestions. Info clicking on the LaCie disk in Finder shows 'custom access' with no way to change. Its permissions are shown as read/write for all 3 categories, but they are greyed out, so I cannot change them. I have added the LaCie drive (formatted in exFAT) to the list of shared folders. Entering my user name and password gives a message '.you might not have permission to use this network resource.' I cannot open either of my 2 connected USB drives - I am asked for a user name and password and the message 'Access is denied' is permanently shown. I have zero access to files on iCloud folders (that may be the correct situation).
ACCESS MAC SAMBA SHARE FROM WINDOWS FULL
I have full write access to files on the Mac internal drive. From the PC I can see the Mac and connected drives.I have full write access to all files on all drives on the PC from the Mac.Both the Mac and the PC can see each other and the opposite systems are listed under network (although I constantly have to re-connect from the Mac to the PC).Some time during 2020 some of the networking features stopped working. I could open shared folders and exchange files both ways. Until some time in 2020 my network between the 2 worked fine. I have a PC running Windows build 18363.1256 (updated today) and a MacBook Pro running Big Sur. This may be a Windows problem but I can't get much sense out of the Windows side of things.