Holy cow, I wrote a book!
One customer discovered that viewing the properties of a drive
from Explorer shows the amount of disk free space
significantly lower than the actual amount of
free disk space as resported by the disk management snap-in.
The command prompt agrees with Explorer and shows the incorrect result.
What's going on?
both Explorer and the command prompt use the
GetDiskFreeSpaceEx function to get the amount of
free disk space.
(It's not surprising because the only two convenient options are
and the former exists only for compatibility with older programs
who don't support drives bigger than 2GB.)
If you go to the documentation for the
you'll see that the amount of free disk space reported
is not the actual amount of physical free disk space
but rather the amount of available physical free disk space
as constrained by the user's quota.
Just saying the word "quotas" to the customer
was enough to satisfy them.
I guess that was enough of a nudge that they could figure out the
rest for themselves.