Updates are good, they improve our system security and add more feature to our software.

In this case after updating a Centos 7.3 installation to 7.4 suddenly a customer old printer cant store scan jobs in a samba share.

After enable verbose log in samba configuring option

log level = 2

we saw some entries like

ntlm_password_check: NTLMv1 passwords NOT PERMITTED for user printeruser

unfortunately our printer was to old and maker does not offer support. we need to allow ntlm authentication in samba enabling ntlm auth option

security = user
passdb backend = tdbsam
map to guest= Bad User
ntlm auth = yes