Knowledgebase: Zix Encryption
What do I do when a bounce reports "zixvpmgateway@zixvpm.DOMAIN: User not found" when trying to send a message?
Posted by Carlos Rios on 17 November 2017 07:06 PM

When an email is encrypted for a ZixGateway, it is addressed to:

The 'User not found' error indicates that the recipients DNS or other internal mail relay has not been configured properly to relay the encrypted email to the ZixGateway.

The encrypted email may be arriving at the receiving email server still encrypted. The encrypted email should be routed to the ZixGateway server for decryption.

ERROR: This domain name does not match domain registered in the license key file (, allowed domains:,localhost, please change the product path to match the domain under Admin CP > Settings > General Settings
This product will not work properly unless untill that value is changed.

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