2010/07/07 by Maarten Oelering.
Delivering large volumes of email can be difficult. Properly handing the bounces can be even more challenging. To decode, analyze and classify the hundredths of different bounce mail formats is a complex task. To give you an idea what you might encounter, here are some examples of bounces: 421 4.7.1 Intrusion prevention active for [X.X.X.X] […]