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POP3 Round Trip




I would like to create a Round Trip sensor in order to test if i can send an email (it is the better test to see if my Exchange server works or not).

But with POP3 or IMAP with this sensor i have an error message:

"Connection to SMTP Server: Error establishing secure connection ([TLS10-12] Socket Error # 10060 Connection timed out. [TLS10] Socket Error # 10060 Connection timed out. [SSL30] Socket Error # 10060 Connection timed out. [SSL20] Socket Error # 10060 Connection timed out.)"

It is strange because i wrote my own email address in "from" and "to" and it works normally.

I have differents sensors to supervise my Exchange server so SNMP should work.

Maybe that it comes from "Helo Ident", i wrote my domain name here.

I tried searching solutions in this forum but i still can not solve my problem, sorry if you have already answered.

Thank you in advance.

10060 imap-sensor pop3 prtg roundtrip smtp-imap snmp

Created on Apr 21, 2015 12:07:45 PM

4 Replies



Dear Stagiaire2

Please clarify: Do you think SNMP should work, or that SMTP should work?

Do you have any other working SMTP sensor to this device? Does the Exchange server / firewall allow the PRTG host SMTP relay?

Created on Apr 22, 2015 1:24:08 PM by  Arne Seifert [Paessler Support]




In my Exchange i have lot of sensors like "Sensor Retry Mailbox Delivery Queue Length _total" or "Sensor POP3" or "Sensor SMTP" so for me SMTP is working in this device.

I will check with my boss if our firewall allow the PRTG host SMTP relay next week.

Created on Apr 24, 2015 8:50:54 AM



Okay, please come back when you have that information.

Created on Apr 24, 2015 9:36:47 AM by  Arne Seifert [Paessler Support]



My problem is resolved, in fact in my architecture i have one physical server and 2 virtuals servers inside.

And even if i have an MSExchangeIS sensor in a virtual server i have to choose the second one to apply the Round Trip sensor.

So it was not the firewall.

Thank you anyway for your time,


Created on Apr 27, 2015 9:30:54 AM

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