I got this from another forum but it worked for me - It turned out that the guest account status is turned off in Win 10 as a security measure. When I turned it back on everything was as before.
Have a look at the Guest account status using the Local Group Policy Editor
Run gpedit.msc and then navigate to:
Computer Configuration - Windows Settings - Security Settings - Local Policies - Security Options - Account: Guest account status
Make sure it is enabled and reboot, I then to find it I did a //Tower and it now shows the files.