Sending from a non-existent email address


New Email
We have an internal database that we use to track modifications to the product we develop. Both this database and the database we sell are built on 4D (an unusual database program that can run on Windows and Mac). One of the features in the internal database is sending emails to employees when certain conditions are met. For some reason, not all these emails are delivered to the recipient. We use hosted Exchange provided by Sherweb. I have checked to see if the emails were caught as spam, but they don't seem to get to our Exchange Server at all. Sherweb has not been able to help with this. My first question is this: The developer set up the function using the following email addresses as the FROM addresses, and is not a valid email address, and we don't own the domain name. My question is, could this be why some of the emails aren't received? It wouldn't seem so, since most people receive the emails. I'm not a developer so can't dig into the program to find the problem, but am tasked with fixing it. Any ideas or input would be welcome. Let me know if I need to clarify anything.