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[no way]

Hello Everyone – 

Does anyone have any diagnostic recommendations or solution ideas to an SMTP error received while sending bulk email? 

The error is: 

“The SMTP mail system returned the following error “Failure sending mail. Unable to read data from the transport connection: net_io_connection closed””

We are using Gmail.

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Thank you in advance for any ideas or feedback! 

Mickey

[Ian Ray]

I’m not sure, but I have some guesses…

You may either be hitting the ceiling for the number of recipients to one message (100) or the number of messages per day (2,000).

If not, have you tried setting up smtp-relay.gmail.com ? I have read that may work in certain conditions where login does not.

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Ian Ray
Cypress Grove
Arcata CA
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[no way]

Thanks Ian! We are comfortably under 2000 and the error is erratic in it’s timing. 

We are considering whether or not it’s b/c of a timeout issue.——————————————-

[Jojo Pornebo]

Does it randomly work?

It could be the SMTP port you are using. Try port 587 in your SMTP port configuration or the TLS port that gmail requires. Your email protocol may be using SMARTTLS.

Jojo Pornebo

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Jojo Pornebo
Subok Na
AUBURN CA
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[Val Gameiro]

It could be a timeout issue. You set a wireshark on your server to evaluate traffic to the SMTP server.

Could also be a DNS issue – when you get that error, have you noticed any problems with DNS? Can you ping and traceroute the server?

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Val Gameiro
Senior NAV Analyst
BPL Plasma
Austin, Texas
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