what's the difference between size and size on disk?

When I select all my files on my C: and go to properties, my size is 109gb and my size on disk is 105. What's the difference?

I'm also noticing that my free space doesn't go back up when I uninstall something. I uninstalled a game that was 3gigs but my free space only went up by about 20 megs. Is there a way to fix this?

My drive is NTFS and I've ran chkdsk but that didn't fix it.

 

Information on cluster size and mis-reported volume size according to microsoft.

 

Thanks for the link. I've read through it (or most of it) and it explains the "size on disk" question. But I didn't catch it explaining how I didn't gain 3gigs back when I should've. I deleted other large files too but they didn't get counted niether. Any ideas on how to correct this?

 

Did you empty the recycle bin?

 

I wasn't thinking in my last post I guess. More than likely that's not the problem or at least not all of it. I forgot you said you unistalled a program. It wouldn't go to the bin if that were the case. It might be the answer though for the large files you deleted. Have you looked in Windows Explorer to see if the uninstaller really did remove the program?

 

Yep, I've checked all that. I think it's something to do with Windows misreporting drive space but I don't know how to fix it.

 

Uninstalling a program doesn't necessarily remove the folders/files from your hard drive. Check the Programs Files folder for these and delete any found, then empty the recycle bin again.

 

Yes, I've done that. 3gigs is still missing. Even more now because I deleted other big files too and none of them "updates" the free space that I should have availible.

 

Often this turns out to be due to the Norton Protected Recycle Bin.