Erroneous Disk Full - Incorrect Used and Available

On one of my systems, I am suddenly experiencing problems with disk full errors. The system has a 370 gig hard drive with 350 gigs free. The df command output is below. The used does not come close to the size of the disk, but available is zero (0). (the s drive is a mapped network drive of the c: share, and no I didn't set it up that way). C:\Documents and Settings\Administrator>df Filesystem 1K-blocks Used Available Use% Mounted on C:\cygwin\bin 390700768 26699324 0 100% /usr/bin C:\cygwin\lib 390700768 26699324 0 100% /usr/lib C:\cygwin 390700768 26699324 0 100% / c: 390700768 26699324 0 100% /cygdrive/c q: 488375968 184629968 303746000 38% /cygdrive/q s: 390700768 26699324 364001444 7% /cygdrive/s any help will be greatly appreciated. Thanks, Leonv