In most cases, ORF is not the only software scanning emails on your server: other components (like the email filtering module of your resident anti-virus scanner, Content Filtering feature of Exchange, etc) may reject, alter or divert the email before ORF could test it.

By default, ORF has lower priority than other components. If you want ORF to filter emails first, the priorities have to be changed.

Changing Priorities on Exchange 2013

In Exchange 2013, the role of the server affects which Transport Agents are installed. Also, an extra parameter is required in the command which tells the Exchange Management Shell on which role the priority should be changed.

Edge Server installation

1. Start the Exchange Management Shell

2. To check the priorities on the Edge Server role, enter the following command:

   Get-TransportAgent -TransportService Edge | Format-List

3. To change the priority of the Vamsoft ORF SMTP Receive Agent on the Edge role, enter the following command:

   Set-TransportAgent -Identity "Vamsoft ORF SMTP Receive Agent" -TransportService Edge -Priority 1

4. Finally, restart the MSExchangeTransport Service to apply the changes:

   Restart-Service MSExchangeTransport

Client Access Server-only installation

Only the Vamsoft ORF SMTP Receive Agent is installed on this role. As of writing this, the Exchange Management Shell should not be used to manage Transport Agents on Client Access Server installations, but local PowerShell is required with the Exchange Windows PowerShell snapin loaded. See "TransportAgent cmdlets on Client Access servers require local Windows PowerShell" section in this Microsoft® TechNet article for details.

1. Start the Windows PowerShell

2. Issue the following command to load the Exchange Windows PowerShell snapin:

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

3. To query the Transport Agents, use the following command:

   Get-TransportAgent -TransportService FrontEnd | Format-List

   You should set the priority of the Vamsoft ORF SMTP Receive Agent higher than the priority of other Transport Agents, so it would run before them (the lower the number the higher the priority).

   The following command changes the priority to 1:

   Set-TransportAgent -Identity "Vamsoft ORF SMTP Receive Agent" -TransportService FrontEnd -Priority 1

4. Finally, restart the MSExchangeFrontEndTransport Service to apply the changes:

   Restart-Service MSExchangeFrontEndTransport

Mailbox Server-only installation

1. Start the Exchange Management Shell

2. Enter the following command:

   Get-TransportAgent | Format-List

3. ORF has two agents, the Vamsoft ORF Routing Agent and the Vamsoft ORF SMTP Receive Agent. You should set the priority of the latter higher than the priority of other Transport Agents, so it would run before them (the lower the number the higher the priority).

   The following command changes the priority to 1:

   Set-TransportAgent -Identity "Vamsoft ORF SMTP Receive Agent" -Priority 1

4. Finally, restart the MSExchangeTransport Service to apply the changes:

   Restart-Service MSExchangeTransport

Client Access Server + Mailbox Server (hybrid) installation

ORF installs the Vamsoft ORF SMTP Receive Agent for both roles, so their priorities have to be set separately on the Client Access server and Mailbox roles.

Client Access Server role

1. Start the Exchange Management Shell

2. To check the priorities on the CAS role, enter the following command:

   Get-TransportAgent -TransportService FrontEnd | Format-List

3. To change the priority of the Vamsoft ORF SMTP Receive Agent on the CAS role, enter the following command:

   Set-TransportAgent -Identity "Vamsoft ORF SMTP Receive Agent" -TransportService FrontEnd -Priority 1

4. Finally, restart the MSExchangeFrontEndTransport Service to apply the changes:

   Restart-Service MSExchangeFrontEndTransport

Mailbox Server role

1. Start the Exchange Management Shell

2. To check the priorities on the Mailbox Server role, enter the following command:

   Get-TransportAgent -TransportService Hub | Format-List

3. To change the priority of the Vamsoft ORF SMTP Receive Agent on the Mailbox role, enter the following command:

   Set-TransportAgent -Identity "Vamsoft ORF SMTP Receive Agent" -TransportService Hub -Priority 1

4. Finally, restart the MSExchangeTransport Service to apply the changes:

   Restart-Service MSExchangeTransport

Please note that the priorities are restored to their default state after you upgrade or re-install ORF. Other software may also change the priorities without prior notice (e.g., Exchange updates).