I have an Outlook 2007 rule set up to reply to sender with a custom reply template if the subject or body contains specific text. This rule works the first time for a specific sender, but doesn't work if the sender sends me another email in the same day. I even confirmed this by setting my PC clock ahead by a day. Sure enough, the auto reply was sent successfully. This tells me that there is something in Outlook that's specifically keeping auto-replies from going out in the same day to the same sender.
I am aware that perhaps this is a preventative measure to keep two machines from entering a feedback loop with one another, but I want to circumvent whatever is causing this so that my rule works unconditionally every time even if it's 100 times a day.
Update: I've discovered that it's not only per day, but per running instance of Outlook. This means you can have your rule send out an automatic reply, shut down/restart Outlook, and have it send out another auto reply. If it's in the same instance, though, it won't work. There has to be a way around this. Maybe the answer lies in VBA, an option I am about to explore.
Best Answer
Answering my own question here. My research has pointed me to the fact that this, as I said in my question, is a preventative measure implemented by Microsoft to keep two senders from entering to a spam feedback loop. The only way I know that this can be done is by writing a VBA macro. I have started writing it, but I will not have the time to finish it in this week or next. If I ever do finish it, I will come back here and post it. For now, since the bounty clock is ticking, I am just going to answer this now to close out the issue.