Adjusting the standard settings of the Windows SMTP server
iQ.Suite Tips & Tricks for Microsoft Exchange / SMTP
iQ.Suite SMTP is a SMTP-based Windows service, which contains a number of standard settings, such as the maximum email size. We will show you how to change these settings.
Step by Step:
- The Windows SMTP service is configured via the Internet Information Service Manager.

- In order to change the standard values of SMTP service, right-click “Default SMTP Virtual Server” and select “Properties” in the context menu.

- The threshold values for email sizes, the maximum number of email recipients, etc. can be found on the “Messages” tab. The standard value of a maximum size of 2 MB per email is generally too low and thus often results in a large number of ‘delivery failure’ messages. This value can be adjusted in “Limit messages sizes to (KB)”.
