I do not remember doing anything unusual to my Mac, but when I tried rebooting into Windows partition, nothing happened. If I didn't hold alt while booting, I got white screen stuck for ages. If I held alt and picked Windows partition manually, OS selection screen would become frozen. Apparently, since my BC partition is NTFS, I am unable to check it, but Boot Camp virtual machine works just fine for some reason. What is wrong, and how can I fix it without doing a reinstall?