I originally applied for a PM internship in Jan 2017, had my first on campus interview with a Principal PM. They gave a full disclaimer saying almost all positions were filled and this could be a early Fall '18 recruiting event. Went well but things didn't click; three weeks later they told me the summer positions were filled but would help me with a sped up full time process.
They reached out to me in early Aug '17 asking if I was still interested. Then they got back in early September saying they'd fly me out to Redmond. Had the final round at Redmond in Oct '17. The entire process was very enjoyable, recruiters constantly helping me with the interview scheduling, accommodating my busy school schedule etc. They put me in a fancy hotel in Bellevue Downtown and covered all trip expenses with a generous meal reimbursement, and sight seeing allowance.
The first interview on campus was with a recruiter, the standard elevator pitch. Then they scheduled an interview with a Principal PM three weeks later. We spoke about the PM position in general, my understanding, their expectations. Standard resume walk through, situational behavioral questions, my masters thesis and how could it apply to Industry.
Final Rounds: Mine was the standard campus recruiting days 80 kids interviewing for SWE/PM roles. They do it in 2 slots, morning and afternoon. Mine was noon on a Friday. We reached at around 11, and all interviewees had lunch on the MSFT campus(paid by them). Then the interview started at 1pm. So, ideally 4 of the interviewees are interviewed mostly by 4 members from a single business group. One Group PM, One Principal PM, One Senior PM, and One PM I or II. So I'm guessing acceptance is at 25%. 4 switch with the other 4 over a period of 4 hours. MSFT used to do 4 or 5 interviews back in the day, for the sake of brevity I think they do 3-4 now. 4 meaning you'll mostly get it. Each interview lasts 45 mins to an hour, and the interviewers speak amongst themselves, so try not to repeat and ramble same stuff over.
My interviews didn't have any coding questions all over, probably because I had a strong technical background or because the other interviewees didn't have a thorough technical background and to have us tested on a bias free ground.
1st interview was about my previous internship experience(s) and end to end white boarding of my Product internship project(Roadmap, Strategy, Tech Flow/Stack, Team Issues, Quantifying Results, Outcome & Impact), and touched on one of my SWE experiences.
2nd Interview was end to end white boarding of my SWE Internship last summer, the bigger picture, (why did i build it, who did it help, explain it to your grandma, impact, value addition etc), Favourite product, what would I fix? One behavioral qn asking how I blew something up or something blew up and who was responsible for it?
3rd Interview was area of interest, then talk about a startup what problem would i solve, suggest a product, monetize it, build it from scratch, markets? users? tech stack...Was challenging.
4th Interview was behavioral situational styled interviews and also why prod etc.. Talk abt a time you fought bureaucracy, stood by what u believed, what would u do if devs dont cooperate, your idea or devs idea, rally folks etc.. Also threw in a prod design qn, same like 3rd but not too much of implementation.
The Interviews were such a beautiful experience and felt they asked me things I'd really utilize in my job. Very respectful and smart Interviewers who knew what they wanted out of the process, only downside I barely got any time to pick their brains. Probably because I talk a lot.
Preparation: Cracking the Pm Interview, Glassdoor, Decode and Conquer the PM Interview, Design of Everyday Things(If you have time, or once you get the job), Medium Articles.
Negotiation: MSFT offers a really sweet package, but asking more never harmed anyone. Use Haseeb Qureshi's medium article on negotiation. One pointer: Don't simply ask for more money, find innovative things to ask or good reasons for more money.