This utility is mostly used by organizations that run CRM Professional, since the Exchange email server can be located on a different server than the CRM Server. If you have not installed the SMTP mail service on the CRM Server and you do not wish it to perform outbound email functionality, you would use this utility to reconfigure CRM to utilize an existing SMTP server, such as Exchange.

For more information about this process, please review the following KnowledgeBase article: http://support.microsoft.com/kb/906471

Here is a screen shot of the user interface:

You will need to have your CRM Installation CD1 on hand before running CRM SMTPSettings because it requires a utility found on the CD ( Microsoft.CRM.Tools.EncryptPwd.exe ) to operate.

CRM StartStop can be found in the Premium Content section on my company web site.  Registration is required but the utility is free.