Resolved Mail sent by client-email always Gmail spam folder

[MicheleB]

Hello,
in the last weeks all the emails sent by a client (e.g. outlook, thunderbird, etc.) are moved on the spam folder of Gmail.

If I send the same email from the webmail (from the server where is hosted the website) arrive correctly (no spam folder) and Google reported for "spf" the label "pass" (with the IP of the server).



The same email sent by client-email arrive in the spam folder of Gmail and the "spf" is labelled as "neutral" (with the IP of my Internet connection).



All my domains have these spf records registered in the dns:
v=spf1 a:mail.mydomain.com ?all

Could be the SPF configuration the problem? Is above configuration correct?
Otherwise, any suggestion to fix this issue?
Thanks.

 

[MicheleB]

I've fixed removing the IP of the server from the gateway incoming settings in the GSuite service.