The Microsoft process is a very thorough process that takes you to campus for a series of interviews (typically an entire afternoon or morning). In my case, I had 4 back-to-back 1:1 interviews and 3 of them were behavioral "fit" interviews where the interviewers just wanted to get to know me. Three of those were with fairly senior people, one was with a more junior member of the team. My one case interview went poorly (on my part): I had been asked to prep for Marketing-style questions ("what's the best marketed product," "how would you improve X product," etc.), and the only question my case interviewer asked me was "How would you price our product?" The interviewer helped me narrow it down later, but didn't add much to clarify while I tried to think about all the different pricing issues with software products. I probably got dinged on that interview alone. Very unfortunate, since I've interned there and I love Microsoft. Lesson learned: be very sure to know exactly what group you're interviewing for, if possible.