We have a piece of 3rd party software that all our outgoing emails are sent from, it is configured to send to an SMTP server. We need to intercept these mails so we can alter them with dynamic signatures, change the from address and multiple other things based on a custom set of rules.
We cannot send the emails via Exchange due to an incompatibility with the 3rd party software.
Our idea is to have a intermediary SMTP server that receives the mail from the 3rd party software and writes out the emails to disk as EML files. I would than have a .NET program listening for these files to be written to disk which would make the necessary alterations and send them to the actual SMTP server.
There are a few apps I've seen around that look to be mainly used for testing email code before you want to send out real emails but I don't think these would scale to our volumes.
Does anyone know of a piece of software that can do the receiving and writing to disk portion, and at scale?
We will work on getting the 3rd party software to fix its issues, but unfortunately that doesn't seem like it's going to possible within out timelines.