Yesterday I noticed that the Exchange 2010 EdgeTransport process was constantly using 25-30% CPU.
Updating Exchange to Exchange 2010 SP3 Rollup 4 didn’t help so I had to dig a bit deeper.
When looking in the Queue Viewer (Exchange Management Console > Toolbox > Queue Viewer) I noticed a message stuck in the Submission queue. Might this cause EdgeTransport to use excessive CPU?
The message had an empty FromAddress (<>). Back in 2011 someone has already posted a solution. Unfortunately, that solution didn’t work for me.
The following (inspired by one of the comments there) did fix the high cpu on EdgeTransport:
- Stop Microsoft Exchange Transport Service
- It should appararently stop the EdgeTransport process, but it didn’t in my case. So I decided to kill the process (after checking there were no emails in other queues)
- In the C:\Program Files\Microsoft\Exchange Server\Transport Roles\data\ folder there is a Queue folder. Rename this Queue folder to Queue_Old
- Start the Exchange Transport Service
- Now a new Queue folder is created and if you check the submission queue, you see that the message is gone.
This fixed the high CPU on EdgeTransport.exe for me.