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Round Trip Sensort fails "Helo command rejected: need fully-qualified hostname"



Since 22.2.77 roundtrip sensor doesn't work properly:

Sending Mail: <MyPrtgMachineName>: Helo command rejected: need fully-qualified hostname
I set a correct HELO identifier in the mail-setup of prtg (https://myprtgserver/systemsetup.htm?tabid=3) and in the round trip sensor. But it seems a change that came with the latest update forces the mail-part of PRTG to use my windows machine name as HELO identifier and uses a non-fqdn-version of that.

mail prtg roundtrip smpt

Created on Jul 28, 2022 2:43:36 PM

Last change on Jul 29, 2022 5:40:44 AM by  Felix Wiesneth [Paessler Support]

1 Reply




We'll need screenshots of the sensor settings. Can you please open a support ticket and submit those?

Benjamin Day
[Paessler Support]

Created on Jul 29, 2022 3:50:22 PM by  Benjamin Day [Paessler Support] (1,441) 2 1

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