turn on computer and hit F11. it uses the hidden partition to restore your system.
s*r
2 楼
Control Panel -> Computer manage? -> Local disk ? Sorry I can't remember the exact names because I'm not using a wintel box now. The so called hidden partition is actually a partition without disk path.
u*s
3 楼
F1 go to CMOS setup, disable the "predestop" area, then you will be able to see the partition in PM.