You can't use the Exchange Management Shell to manage transport agent in the Front End Transport service on a Client Access server. Instead, you need to open Windows PowerShell on the Client Access server, and then import the Exchange cmdlets into the Windows PowerShell session.

Caution:

Running Exchange cmdlets in Windows PowerShell for tasks other than managing transport agents in the Front End Transport service is not supported. There are serious consequences that can result if you bypass the Exchange Management Shell and role-based access control (RBAC) by running Exchange cmdlets in Windows PowerShell. You should always run Exchange cmdlets in the Exchange Management Shell. For more information, see Release Notes for Exchange 2013.

To perform any of the Transport Agent procedures described in this topic in the Front End Transport service, you need to perform the following additional steps:

1. On the Client Access server, open Windows PowerShell and run the following command:
   
   

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   Add-PSSnapin Microsoft.Exchange.Management.PowerShell.SnapIn

2. Run the command as described, but add the following value to the command: -TransportService FrontEnd.
   
   For example, to view the transport agents in the Front End Transport service on a Client Access server, run the following command:
   
   

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   Get-TransportAgent -TransportService FrontEnd

When you install a transport agent, Exchange only registers the DLLs associated with the transport agent. You need to make sure all files, registry keys, and other objects that the transport agent depends on are installed correctly and configured. After Exchange loads the DLLs, it continues to reference the DLLs after the command has completed.

Transport agents have full access to all e-mail messages that they encounter. Exchange puts no restrictions on a transport agent's behavior. Transport agents that are unstable or contain security flaws may affect the stability and security of Exchange. Therefore, you should only install transport agents that you fully trust and that have been fully tested in a test environment.

Transport agents are installed in a disabled state to make sure mail flow isn't affected by transport agents that haven't been configured. Therefore, after a transport agent has been configured correctly, you need to enable the transport agent.

Use the following syntax to install a transport agent.

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Install-TransportAgent -Name <TransportAgentIdentity> -TransportAgentFactory <"TransportAgentFactory"> -AssemblyPath <"FilePath">

This example installs a fictitious transport agent named Contoso Transport Agent in the Transport service on a Mailbox server.

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Install-TransportAgent -Name "Contoso Transport Agent" -TransportAgentFactory "vendor.exchange.ContosoTransportAgentfactory" -AssemblyPath "C:\Program Files\Vendor\TransportAgent\ContosoTransportAgentFactory.dll"

How do you know this worked?

Use the following syntax to enable a transport agent.

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Enable-TransportAgent <TransportAgentIdentity>

This example enables the transport agent named Contoso Transport Agent in the Transport service on a Mailbox server.

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Enable-TransportAgent "Contoso Transport Agent"

How do you know this worked?

Use the following syntax to disable a transport agent:

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Disable-TransportAgent <TransportAgentIdentity>

This example disables the transport agent named Fabirkam Transport Agent in the Transport service on a Mailbox server.

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Disable-TransportAgent "Fabrikam Transport Agent"

How do you know this worked?

To view a summary list of transport agents, run the following command:

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Get-TransportAgent

To view the detailed configuration of a specific transport agent, run the following command:

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Get-TransportAgent <TransportAgentIdentity> | Format-List

This example provides detailed configuration of the transport agent named Transport Rule Agent.

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Get-TransportAgent "Transport Rule Agent" | Format-List

Transport agents with a priority closest to 0 process email messages first. However, the SMTP event in the transport pipeline where the transport agent is registered may cause a lower priority agent to act on the message before a higher priority agent.

To modify the priority of an existing transport agent, run the following command:

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Set-TransportAgent <TransportAgentIdentity> -Priority <Integer>

This example sets the priority agent value of 3 for the existing transport agent named Contoso Transport Agent in the Transport service on a Mailbox server.

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Set-TransportAgent "Contoso Transport Agent" -Priority 3

How do you know this worked?

When the transport agent is uninstalled, Exchange unregisters the DLL files used with the agent. Exchange doesn't remove any files, registry keys, or other objects added by the installation of the transport agent.

To uninstall a transport agent, run the following command:

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Uninstall-TransportAgent <TransportAgentIdentity>

This example uninstalls the transport agent named Fabrikam Transport Agent from the Transport service on a Mailbox server.

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Uninstall-TransportAgent "Fabrikam Transport Agent"

How do you know this worked?