A lot of people ask me question regarding the process to upgrade Microsoft Exchange server 2013 to 2013 SP1.
There is nothing special to pass this update. Before we see how to begin this migration you need to know :
The first step os to prepare your AciveDirectory and AD schema :
setup.exe /PrepareSchema /IAcceptExchangeServerLicenseTerms setup.exe /PrepareAD /IAcceptExchangeServerLicenseTerms
Then you upgrade your server throught the PowerShell or the GUI. if you decide to go with PowerShell use this command :
setup.exe /m:upgrade /IAcceptExchangeServerLicenseTerms
If after this installation the mail flow is not working that means the transport service cannot restart correclty. It can occur on server with role CAS installed. In this case restart the server will fix this.