Had some trouble tonight with a damaged mbr on a netbook and had to restore grub, here are the easy steps to start windows from a grub2 prompt:
- ls (lists available partitions)
- set root=(hdX,msdos1) (or similar, check ls output)
- chainloader +1
Additional tips: once you’ve set root you can browse the file system with ls, beforehand „ls (hdX,Y)/“, note the slash, works too. Can be handy to see if one tries to boot the correct partition.
Great page for more info: https://help.ubuntu.com/community/Grub2