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Announcement 1 Required Mimecast Smart Host Migration by July 15th
Announcement:Required Mimecast Smart Host Migration by July 15th

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Usage Considerations Configuring an Anti-Spoofing Policy Example Policies Anti-Spoofing Policy to Allow Spoofing Based on IP Anti-Spoofing Policy to Block Unwanted Spoofed Emails Spoofing is the forgery of email headers so messages appear to come from someone other than the actual source. This tactic is used in

When messages are sent or received between two email servers or Mail Transfer Agents (MTAs), the communication uses a series of numeric SMTP codes. These codes are always in pairs, which means both servers transmit the codes until either the conversation is successful, or fails.   There are two main code types for dropped or failed SMTP