421 Command timeout

If you have received the following error messages in your email logs file, it might be due to numerous reasons.

421 Command timeout, closing transmission channel
Exception occurred: Type= Exception= -|<class 'ct_smtplib.SMTPServerDisconnected'>:Socket error sending DATA|

Possible Soultions:
- It cause be the remote server that is dropping your email due to the filtering rules.
- it could be network issues with MTU. You will need to get both network operating center to resolve this.

If you are on our managed solutions, please contact us to for assistance.

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