[Gilda G]

I had the same problem in my 2006 E60, it ended up being the seal around the sunroof. I replaced the seal and sunroof mostly through insurance and out of pocket. Also I pulled my carpet up and found almost 2 inches of water which ended up damaging all the electronics under the passenger seat. I took pictures and pulled the drain plugs since bmw puts a lot of electronics under the floor boards which end up to be very costly to fix if they get wet. Months later the water came in again so I sold the car since BMW couldn't find the issue this time around. Check the drains in the sunroof and under your hood by shooting compressed air through them if they are clogged it will drain behind your front tires and in front of your back tires mind you if BMW finds them clogged they will not cover the cost since cleaning them is the sole responsibility of the owner. Also check your trunk in the storage area where a spare tire would normally go, water could get in there from the drains...
Good luck with your outcome.