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Why am I receiving "Recipient Verification Unavailable" errors when not using LDAP on the Email Security Gateway?

  • Type: Knowledgebase
  • Date changed: 2 years ago

Solution #00005984


Scope: 

This solution applies to the Email Security Gateway, all firmware versions.


Answer:
In some situations, the destination mail server will return a 450 "Invalid Recipient" response back to the Spam Firewall, causing this error to appear.

Solving any issues on the destination mail server that would generate 450 errors will cause these notifications to cease.


Link to this page:

http://www.barracudanetworks.com/kb?id=50160000000IlyH