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Cannot send mail

Thunderbird Email and messaging
leif.hammarstrom replied 2 years ago
leif.hammarstrom
leif.hammarstrom

Sending a mail results in the following message:

Sending of the message failed. An error occurred while sending mail: Outgoing server (SMTP) error. The server responded: Disallowed HELO string.

Sending a mail results in the following message: Sending of the message failed. An error occurred while sending mail: Outgoing server (SMTP) error. The server responded: Disallowed HELO string.

Modified by leif.hammarstrom

All Replies (1)

leif.hammarstrom
leif.hammarstrom Question owner

Chosen Solution

Found the solution in

https://kb.mozillazine.org/Replace_IP_address_with_name_in_headers