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POP3 Roundtrip error



I'm running PRTG, and setup the POP3 Roundtrip sensor. However, its status always shows down with the messages "Maximum Trip Time exceeded (giveing up)" or "Unexpected connection drop (code: PE039)".

I've also add the SMTP and POP3 sensor to the same server and both are running normally (response time around 2-3 msec).

The probe and the mail server are on the same local network, so there should not be affected by the network condition. Anyone have idea on that issue?

Thanks in advance.

pop3 roundtrip smtp

Created on Jul 30, 2013 6:42:34 PM

3 Replies




thank you very much for your KB-Post. Just to check, do you use a dedicated inbox for the Roundtrip Sensor? Do emails arrive in the inbox?

best regards.

Created on Jul 31, 2013 12:38:01 PM by  Torsten Lindner [Paessler Support]



Yes and yes. Today I try to change the pop login to use SSL, and the sensor works. However for normal pop3 login it still got the same error. In the same time all POP3 user of the mail server work flawlessly.

Created on Jul 31, 2013 1:05:16 PM



In that case we would suggest to use the SSL Login on the Pop3-Part of the sensor.

Created on Jul 31, 2013 1:19:41 PM by  Torsten Lindner [Paessler Support]

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