30 seconds to run a check on a 500Gb drive? That's too fast to be
believable.
My Vista laptop only has a 285Gb drive and it took almost 25 minutes.
When chkdsk first started, it just sat there for a while doing nothing.
I was about to close it thinking it wasn't doing anything when it
suddenly started reporting "stage 1 of 3" activities, then "stage 2 of
3", etc. It displayed percentage of completion of the disk scan as it
worked.
Are you sure you didn't shut it down before it even started?
chkdsk
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