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SMTP&IMAP Round Trip Sensor



I am trying to setup SMTP and IMAP round trip sensor. Here is my configuration: Email Settings: From - [email protected] - designated email To - [email protected] Helo Ident - not sure - mailserver.company.com, or prtg.company.com Step 1: - default/ no changes Step 2: IMAP mailbox - Inbox Port 143 Usernam and Password The rest - are default The message (PRTG Roundtrip Mail: {8FD98D15-​E22C-473B-​997C-81BC4​F1FFCDD}) comes in the gmail box, then is forwarded back to the dedicated [email protected] box and i can see it there, but the Sensor is alwais RED with error "Connection to IMAP Server: Socket Error # 10061 Connection refused."

Could you help me please!

roundtrip smtp---gmail smtp-imap

Created on Feb 13, 2013 4:44:30 PM

3 Replies




if the round trip mail is forwarded to a mailbox on your mailserver, then that is the IMAP mailbox you need to check for the mail, and not the google mailbox at

maybe take a look at


from minute 7:00 forward

Created on Feb 14, 2013 7:12:17 AM by  Aurelio Lombardi [Paessler Support]

Last change on Feb 14, 2013 7:15:25 AM by  Aurelio Lombardi [Paessler Support]



The emails are flowing to the gmail and to the exchange mailbox. I can see them in both accounts. So they make the round trip, but PRTG sensor is still red and "Connecting to IMAP Server: Socket Error # 10061 Connection refused" error shows up. Trying to figure out what i am doing wrong.

Created on Feb 14, 2013 1:53:59 PM




our configuration looks like this.

we have created our mailserver as a device in PRTG.

On that device we created the roundtrip sensor.

Our PRTG server is allowed to relay through that mailserver so that it can send mails to external mail addresses.

The roundtrip sensor is configured in that way that we send the roundtrip mail to a google account. That google account is configured ti immediately forward all mail to a dedicated mailbox on our mailserver.

And that dedicated mailbox is the one where the roundtrip sensor looks for the mail.

we are using exchange 2010, but it should work with any mailserver.

Created on Feb 15, 2013 9:18:03 AM by  Aurelio Lombardi [Paessler Support]

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