SMTP data timeout (message abandoned) on connection

[keldnner]

I'm having problems where some customers are trying to send emails with attachments and signatures (headers) and are generating messages that are the same as the topic title, and if sent with full text, it usually works.

I already checked here on the forum the old solutions like SMTP data timeout on connection and even the update that it had in 2017, but until the I have not had any success.

I also changed the mtu of the network to test, and it also didn't work.

Just as an observation, some customers have this difficulty.

 

[cPanelLauren]

When the specific customers that have this issue ping the network are they experiencing packet loss? Otherwise, I'd suggest opening a ticket as this would require a more in-depth investigation than we're able to provide through the forums.