lost while reading message data

[algorges]

I am 15 days with a difficult problem to solve.
A lot of my clients are unable to send emails with attachments. When you send email without attachment, send normally.
In emails with attachment generates timeout for the client. After a while the some email clients can send e-mail
I thought it could be clamav. Removed the plugin and had no effect.

In exim logs appears many timeout.

2015-10-15 15:18:21 SMTP connection from xxxxxx.com.br [xxxxxx]:57300 lost while reading message data (header)
2015-10-15 15:18:49 SMTP connection from xxxxxnet.br [xxxxxxx]:50944 lost while reading message data
2015-10-15 15:18:53 SMTP connection from (userPC) [xxxxxxxxx]:63771 lost while reading message data
2015-10-15 15:18:54 SMTP connection from xxxxxxxx [xxxxxxx:38022 lost while reading message data (header)
2015-10-15 15:18:57 SMTP connection from (RR03) [xxxxxxx]:53067 lost while reading message data
2015-10-15 15:19:04 SMTP connection from xxxxxx [xxxxxxxx]:5604 lost while reading message data (header)
2015-10-15 15:19:17 SMTP connection from (xxx) [xxxxxxx]:52205 lost while reading message data
2015-10-15 15:20:10 SMTP connection from (xxxxxi) [xxxxxx]:54720 lost while reading message data
2015-10-15 15:20:33 SMTP connection from (xxxx) [xxxxxx]:54712 lost while reading message data
2015-10-15 15:20:40 SMTP connection from xxxxxxx [xxxxxxx]:35291 lost while reading message data (header)
2015-10-15 15:20:55 SMTP connection from xxxxxx [xxxxxxx]:59821 lost while reading message data (header)
2015-10-15 15:21:04 SMTP connection from (pc01) [xxxxxxxx]:52141 lost while reading message data
2015-10-15 15:21:15 SMTP connection from xxxxxxx [xxxxxxx]:55147 lost while reading message data

 

[algorges]

I did a test today and set up a 587 to use SSL. This achieves usually send emails. Using SSL 587 in case the above problem.

 

[Infopro]

Solved or no? Unsure by your reply.

 

[algorges]

No solved.
SSL works. But the vast majority of users use connection on port 587 without SSL.

I'm still trying to figure out what's going on.

 

[cPanelMichael]

Hello

Please ensure you follow the steps at:

Guide To Opening An Effective Forums Thread

In particular, we need a version number for cPanel to help determine if it's possibly related to the SMTP delay feature that was added in cPanel version 11.52.

Thank you.

 

[algorges]

I have

• WHM 11.52.0 (build 17)

 

[cPanelMichael]

Do you notice any corresponding entries in /var/log/maillog that appear at the same times as the error messages in /var/log/exim_mainlog?

Thank you.