You might try: Going to the following Group Policy setting:
Computer configuration\administrative templates\network\Lanman Workstation
And “Enable insecure guest logons”
SMBv2 behavior was changed and no longer allows a user to connect to a remote share by using guest credentials by default, even if the remote server requests guest credentials.
This and making sure you have SMB v1 turned on. Windows keeps turning it off. So double check that as well.