This happens if the PC is reset or switched off without shutting down Windows properly, e.g.:
User switches off (or resets) PC without shutting down properly
User attempts shutdown, but shutdown fails to complete
Power fails, or is accidentally switched off
PC spontaneously resets (e.g. bad power or power supply)
PC crashes or locks up, so that shutdown is impossible
There is a utility to recover that bad sector, but it costs $40. Here's
something that may be of use.
Humans are the only creatures that won't live up to the their potential. Give everything your all. When you die, die on E.
So I ask you, what do you intend to do now?