How important is week 1 of Summer Internship? What to do if I can't attend

Hi all,

Due to clashes with my final exams, I will not be able to starte my summer internship on time. I've tried to apply for special consideration to the university but was told it's not going to happen. I feel very frustrated now.

Just wondering how f**ed I will be if I miss first week's training. More importantly, how do I make up for it in order to get a return offer?

Thanks.