access denied on smbclient.register_session

Question

i try to connect from my mac to a smb server using this

smbclient.register_session(
 "smbserver.net",
 username="domain\\username",
 password="secret",
 port=445
 )

but i allways get this error

AccessDenied: Received unexpected status from the server: A process has requested access to an object but has not been granted those access rights. (3221225506) STATUS_ACCESS_DENIED: 0xc0000022

to check that the authentication is working i entered a wrong combination which lead to a LogonFailure. so this cannot be it. i also tried changing the username to [email protected] with the same AccessDenied error.

Using finder and a nifi container running on my machine i could establish a connection and load files.