Marin Petkov

Member
Aug 27, 2014
7
0
1
Sofia, Bulgaria, Bulgaria
cPanel Access Level
Root Administrator
Hello, colleagues

For several weeks we experiencing difficulties sending e-mails to one of our customers.

When I look at Mail Delivery Reports see two strange things first is

"Connection timed out: SMTP timeout while connected to mail.server.com [themip] after sending data block (16,379 bytes written)"

When I try:

Code:
telnet mail.server.com 25
Trying xxx.xxx.xxx.xxx ...
Connected to mail.server.com.
Escape character is '^]'.
220 ********************************************
421 Transmission channel timeout.
Connection closed by foreign host.
Obviously they use Firewall / barracuda

The second strange thing I see is in the Mail Queue Manager

Code:
[email protected]/virtual_aliases_nostar,
[email protected],
/home/folder/mail/domainname/emailaccount/.Folder/:[email protected],
And 5-6 more real email addresses from our server. Please help me
 

cPanelMichael

Administrator
Staff member
Apr 11, 2011
47,913
2,201
363
Hello :)

Do you have access to the remote mail server you are sending email to? If not, have you tried contacting them to let them know their firewall is blocking connections from your server?

Thank you.
 
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cPanelMichael

Administrator
Staff member
Apr 11, 2011
47,913
2,201
363
I forgot to say that some of our e-mails are received but every e-mail over 250 kb is timed out
Is this happening when sending to any remote mail server, or is the issue isolated to a single remote mail server that you are sending to?

Thank you.
 

cPanelMichael

Administrator
Staff member
Apr 11, 2011
47,913
2,201
363
You will need to consult with the administrator of that mail server to have them review their logs to see why they are blocking messages from your server.

Thank you.
 
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