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5.5.4 HELO/EHLO argument "(null).gateway" invalid

  • 3 replies
  • 1 has this problem
  • 31 views
  • Last reply by pg.mast

pg.mast
pg.mast

As of this morning I get an error on all of my gmail accounts in Thunderbird.

An error occurred while sending mail: Outgoing server (SMTP) error. The server responded: 5.5.4 HELO/EHLO argument "(null).gateway" invalid, closing connection. 5.5.4 https://support.google.com/mail/?p=helo y18sm36496522pfi.104 - gsmtp.

I have check my settings and all are correct. I am unsure about what's happening?

As of this morning I get an error on all of my gmail accounts in Thunderbird. An error occurred while sending mail: Outgoing server (SMTP) error. The server responded: 5.5.4 HELO/EHLO argument "(null).gateway" invalid, closing connection. 5.5.4 https://support.google.com/mail/?p=helo y18sm36496522pfi.104 - gsmtp. I have check my settings and all are correct. I am unsure about what's happening?

Chosen solution

It fixed itself - so I'm not sure what happened or how.

Matt said

try disabling the conversations add-on and see if that helps.

Thanks for your suggestion Matt.

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All Replies (3)

pg.mast
pg.mast Question owner

Screenshot attached

Matt
Matt
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try disabling the conversations add-on and see if that helps.

pg.mast
pg.mast Question owner

Chosen Solution

It fixed itself - so I'm not sure what happened or how.

Matt said

try disabling the conversations add-on and see if that helps.

Thanks for your suggestion Matt.