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Unexpected connection drop (code: PE039)



IMAP round trip sensor talking to Exchange 2007 server. Gets "Unexpected connection drop (code: PE039)" No test email is received.

Plain SMTP with mail delivery sensor does not work either so I suspect it may be the same problem.

Telnet tests from machine that is running probe (it is the local probe PRTG itself doing the test) works fine; mail can be delivered.

I am using the beta version: PRTG Network Monitor V8

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Installed versions:

Server Service: V8.0.5.1434 Probe Service: V8.0.5.1434 Server Administration Tool: V8.0.5.1434 Probe Administration Tool: V8.0.5.1434 Import Tool: V8.0.5.1434

beta imap prtg smtp

Created on Aug 30, 2010 11:34:02 PM

2 Replies



Dear Roland,

does the error happen frequently? Does it "resolve itself"?

Best Regards.

Created on Sep 1, 2010 11:44:01 AM by  Torsten Lindner [Paessler Support]



It happens 100%. Neither the IMAP round trip sensor, or the plain SMTP sensor have ever connected to the Exchange server successfully.

I assume that both sensors connect to the target via SMTP first to send a piece of email. As this works from telnet xxx.foo.com 25 on the machine running the probe I am guessing that the proble itself is somehow confused.

The machine is "mutlihomed" and the probe is configured to connect to the prtg server on and to use a public IP for "Outgoing" requests. Tried placing the sensor on another problem that is a different location in my network and I got the same failure mode, so I suspect that "networking" is not the root cause of this problem.

Created on Sep 1, 2010 3:31:51 PM

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