Exchange 2013 Cumulative Update 3 broke smtp

anything reported in the event viewer ?

I think the only option you have is to uninstall CU3 and again install CU2 then you have to wait for Exchange 2013 SP1 to be released.

I have an IIS error around the time i tried to install the update:
 
The description for Event ID 1007 from source Microsoft-Windows-IIS-IISManager cannot be found. Either the component that raises this event is not installed on your local computer or the installation is corrupted. You can install or repair the component on the local computer.

If the event originated on another computer, the display information had to be saved with the event.

The following information was included with the event:

IISWMSVC_STARTUP_UNABLE_TO_READ_CERTIFICATE

Unable to read the certificate with thumbprint '156d0a18852448c1abc728917f65e3131696a513'.  Please make sure the SSL certificate exists and that is correctly configured in the Management Service page.

Process:WMSvc
User=NT AUTHORITY\LOCAL SERVICE

the message resource is present but the message is not found in the string/message table


And I also have an error where the installer for CU3 Failed:  

Process ExSetupUI.exe (PID=23212). ServerComponentState for Component 'Monitoring' set by Requester 'Functional' to 'Inactive'.

Ahmed786 -

I would have no problems doing that but I don't see it listed in add programs and features where it can be uninstalled.  The only thing I see is the CU2?

on the exchange connectivity test site i'm getting this response when trying to do an inbound mail:

Testing TCP port 25 on host mail.electionadministrators.com to ensure it's listening and open.
       The specified port is either blocked, not listening, or not producing the expected response.
        Tell me more about this issue and how to resolve it
       
      Additional Details
       
The connection was established but a banner was never received.
Elapsed Time: 16644 ms.

Anything else on the server, that could be using or listening to port 25?
You cannot really uninstall an Exchange rollup and install an older one, the rollups don't work like that. They are the full product.

If you run the CU3 setup again, does it prompt you to continue to update?

Simon.

I've tried to rerun the update several times. It always fails at 90% during the prerequisite check. It won't install. I don't know what else could be listening on 25. Everything was working correctly yesterday. I've checked the settings on our Cisco Asa and the port is open and translating to the correct internal address. I've disabled the windows firewall also.

Update:  I have found the reason that the CU3 would not pass the prereq test.  The Web Management Service was not started.  I had to go into IIS manager and assign a certificate to it then restart it as detailed in this TN article:

http://social.technet.microsoft.com/Forums/en-US/7f193833-de94-408b-91ad-266d6811a26b/exchange-2013-cu2-to-cu3-upgrade-error?forum=exchangesvrdeploy

Its running right now and appears to be making progress, in the mean time i've re enabled the send/receive connectors on our old EX 2k7 server and changed our NAT and DNS entries.  After the CU3 hopefully runs successfully I hope to be able to switch everything back and get going again.

Its good to hear that ur issue has been resolved, may this can help others.

I finally got this going after several hours trying to reinstall the CU3 using the powershell.  It appears to me that even though the CU3 originally only failed during the prerequisite check it somehow broke exchange.  From what I could see all the relevant exchange services were still up and running but it basically wasn't listening on port 25 anymore.   It seems crazy that the update would do that but it also seems like most of the things with exchange 2013 don't work as expected.

CU4 and Sp1 are the same thing - just a different name being applied.

Simon.

SP1 was released today.