...on a partition.

Oh my.

1 attached image

http://windirstat.info/

Use that to fnd out what's eating your drive. It may take a long time depending on drive size and system power.

Do what I do to free up some space - go through the program files and delete anything that you don't use anymore or is completely useless.

Also use this to clean out all the crap that Windows and Firefox etc generate. One time I cleared a few gigabytes of pooooooop.

Yeah, definitely use Jared's CCleaner (linked above/below).

To get rid of space in the meantime, go to the control panel, performance and maintaince, and then "free up disk space" (or something like that). You'll usually need to select a drive (probably the C drive), it will spend about 10 minutes calculating, and you can probably free up a couple gigs with the "Compress Old Files" option.

Also, if the Recycle Bin is full... you may want to clear it.

Actually it's because people are idiots and delete things they shouldn't have, and the recycle bin exists to protect the average person from scrwewing their computer sideways. Don't be a hater.

Low disk space? What's that?

Seriously, you might have too many copy images or videos on your HDD. Filter through your saved documents and weed out what's unnecessary, or drop the resolution/.kps of music and image files. I once ate up five hundred gigs of space cause I had a couple hundred 8-bit songs pumped up to 320kps with uncompressed data tracking.

Also, stop downloading software. :3