Example: your OS (operating system) claims that that specific folder is 300 mb. Though your manufacturer claims it's only 250 .
That might be a reason for the difference, I believe.
Also, remember that when you move files, it's best to uninstall the application, then install it on your F: drive.
I'd suggest attaching an external hard disk, in case you have much files (eg. movies) on your C: drive that you still want to keep.
I think in your case it would be useful to use disk quota.
This will prevent you from putting anything on the C: drive that is for example larger than 50 mb.
Read here how to do that >> http://www.microsoft...s.mspx?mfr=true
More information >> http://www.microsoft...w.mspx?mfr=true