Sometimes it is very hard to troubleshoot SMTP issues that occur with your DotNetNuke application. Sure, you can view the SMTP log of your mail server, but that may be either misconfigured, or not even accessible at all (this is especially true in a shared hosting environment).
Luckily, there is a very simple way to enable logging for all network traffic DotNetNuke is generating, which includes SMTP traffic.
This starts with realizing that the DotNetNuke email implementation is using System.Net.Mail. Apart from the documentation on MSDN about the System.Net.Mail namespace.
On that site, we can find a very easy way to configure logging for the mail system. In fact, the way it is explained there, it will actually set up logging for all network requests done by the application. That can be very useful when troubleshooting.
This is a very powerful option to really troubleshoot communication between DotNetNuke and the configured SMTP server. A fair warning though: if you keep this trace active, it will generate 1 potentially very large file. If you want to keep this type of logging in your application, it is probably a good idea to make sure the log file is a rolling type. The standard TextWriterTraceListener cannot do that, but it is not very hard to create your own listener that can. home automation systems