My referee is not responsive and I am only a week away from the final deadline, the program's admission committee does not allow me to change referee, what should I do?

[yycccllll]

I started to contact my professor for recommendation letter in mid-Nov, and he replied a month later, explaining that he was busy with final exams and was happy to provide me a recommendation. I should have been alarmed by then but instead, considering he was quite a successful senior chief financial manager, which would add up a lot for my application, I listed his name for three most important programs. However, he seems to be unresponsive for all of my follow-up emails. And since he is an adjucnt professor from my exchange school and it is summer vacation now, there's no way that I could ever meet him in person and I cannot call him up as well as I don't have his personal phone number (And I believe it will only make things worse by calling him). I am totally freaking out and I wonder if anyone has any good idea for my situation. 

[fuzzylogician]

If you're really concerned, my best advice is to get an emergency fourth letter from whoever will agree to write you one, and have that person email the letter directly to the program, if they won't allow you to update the online application. That way, at least you have the minimum required number of letters, even if one is missing. You might also give your recommender the benefit of the doubt. With a full week left to go, there are many(!) professors who haven't started working on their LORs yet. That tends to be something a lot of people do very last minute, even after the official deadline because there is often a grace period for letters beyond what's allowed for the rest of the application. This could very well work out for you if you do nothing other than sit and wait.