Users Getting Disabled Automatically – “Invalid Recipient” in Message Log

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• M

  M

  3/3/26, 1:52 AM

  Hello members,

  We are currently facing an issue where some users are being automatically disabled, and as a result, they are unable to receive external emails.

  When checking the Message Log, we see the error:

  “Invalid Recipient”

  To restore mail flow, we have to manually re-enable the affected users.

  We would like to understand:

  1. What could cause users to become disabled automatically?

  2. Is there any message limitation, security threshold, or protection mechanism that disables users after a certain number of invalid recipient attempts?

  3. Could this be related to SMTP call-forward verification, directory harvesting protection, or account verification settings?

  Any guidance on where to check in the settings would be appreciated.

  Thank you.

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• M

  M

  3/3/26, 1:58 AM

  Issue solved! I increased the number of messages in "account hijack detection" .

   

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• A

  Arron Admin Staff

  3/3/26, 7:58 AM

  Thank you for following up and letting us know what was causing the issue!

  --
  Arron Caruth

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