Third-party transport agents cannot be loaded correctly in Exchange Server 2013

support.microsoft.com

After you install Microsoft Exchange Server 2013 Service Pack 1 (SP1) or you upgrade an existing Microsoft Exchange Server 2013 installation to Exchange Server 2013 SP1, third-party or custom-developed transport agents cannot be installed correctly. Additionally, the Microsoft Exchange Transport service (MSExchangeTransport.exe) cannot start automatically. Specifically, you cannot enable third-party products that rely on transport agents. For example, you cannot enable anti-malware software or custom-developed transport agents.

When the installation fails, you also receive an error message that resembles the following:

The TransportAgentFactory type must be the Microsoft .NET class type of the transport agent factory.

Microsoft has developed a PowerShell script that corrects a formatting error in the configuration files that govern the Transport Extensibility that is built into Exchange Server 2013. To have us apply this script for you so that Transport Extensibility and third-party products that use this capability function correctly, go to the "Fix it for me" section. If you prefer to fix this problem yourself, go to the "Let me fix it myself" section.

To read the full article, go to: Microsoft Support