I have a multi-role Exchange 2013 CU3 Server running on a Windows 2012 r2 Standard VM. I have been having issues with intermittent mail flow. When mail stops I need to restart the server to have mail flow again. I had put in a custom receive connector to allow internal devices, photocopiers, custom apps etc, to send mail out. It was configured as a FrontendTransport connector. It worked well for months, then I started having issues. After performing a Get-ServerHealth I see that the FrontEnd Transport is unhealthy (OnPremisesInbound... and OnPremisesSmtpCli...). After performing a Netstat -aon I see that the FrontEnd Transport PID is listening on 2525 along with the HubTransport PID. Going over my receive connectors in both EAC and PowerShell they show that none of my FrontEnd connectors are listening on 2525. I am fairly confident that because the two services are listening on 2525 this is causing my mail flow issues, but I can't see where to fix it. Any help would be greatly appreciated.