I was unable to send email notifications using my gmail account settings. The error was due to the use of unknown HELO/EHLO identifier in the notification delivery settings in my PRTG server.
SMTP delivery Error Gmail 501-5.5.4 HELO/EHLO argument "" invalid, closing connection
Modified on 2025-06-10 21:02:01 +0200
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The information in the Paessler Knowledge Base comes without warranty of any kind. Use at your own risk. Before applying any instructions please exercise proper system administrator housekeeping. You must make sure that a proper backup of all your data is available.
The information in the Paessler Knowledge Base comes without warranty of any kind. Use at your own risk. Before applying any instructions please exercise proper system administrator housekeeping. You must make sure that a proper backup of all your data is available.
