Email Signature Manager version 8.x
Email Signature Manager version 7.x
This article describes the symptoms and cause of a known issue with Exchange Server 2013 SP1 which means third-party transport agents cannot be correctly registered. This article also describes the resolution for this issue.
Following apparently successful installation of the Email Signature Manager Transport Agent on Exchange Server 2013 SP1, the transport agent has not actually been installed.
When executing the Get-TransportAgent cmdlet in the Exchange Management Shell, the Email Signature Manager Transport Agent is not listed.
When attempting to manually install by executing the Install-TransportAgent cmdlet an error occurs about the TransportAgentFactory type being incorrect.
This problem occurs consistently with Exchange Server 2013 SP1 because the global assembly cache (GAC) policy configuration files contain invalid XML code.
Uninstall the Email Signature Manager Transport Agent.
Install Exchange Server 2013 Cumulative Update 5 (CU5) or newer.
Reinstall the Email Signature Manager Transport Agent.
Microsoft has confirmed that this is a problem in Exchange Server 2013 SP1.
The problem is resolved as described above.