ive had no end of problems with my bootcamp portion, which was fine under windows 7 and yosemite, but between el capitan and windows 10, its been a disaster, lots of crashing, mainly when usb drives plugged in. so finally i took the plunge, downloaded windows 10 and stuck it on a dvd, backed up all my steam games (all i use windows for) and opened bootcamp 10 assistant and removed windows. except at the end of it it gave me an error about not being able to remove the partition, and now although disc utility can see that my internal drive is 1TB, i can only see 500gb which is my original mac partition. nothing in disc utility works, if i do it from OS X, it says its combined the partitions but i can see it hasn't. reducing the partition to 1 and pressing 1 just gets operation successful.... running it from recovery mode is worse, it tells me theres an error in the recovery partition. boot camp assistant doesnt think the partition is there any more. it just sees a 500gb drive and asks me if i want to partition that. disc utilities cant find any problems.