I just freed 3GB from my hard drive and now, 5 minutes later, I got the warning "you're running on extremely low disk space". How can I find out which program is eating up my disk that fast? Thanks.
If it is writing 3GB in 5 min, you can open task manager, select the Performance Tab, and press the "Resource Monitor" button. (assuming Windows 7 or Vista)
On the window that opens, select the Disk tab, and expand both "Processes with Disk Activity" and "Disk Activity".
You can sort by Total, or Write, and you should see what Process is writing to the disk the most.
How big is your drive?
Has the 3Gb definitely been used by something?
Take a look at this URL discussing what causes that warning http://blogs.msdn.com/b/oldnewthing/archive/2010/11/17/10092277.aspx
If its not a process thand take that is using up your space, it could be your page file (the file Windows uses for virtual memory, usually sits on the root of whatever drive hosts your operating system). If the page file is choked and can't allocate all the virtual memory space it wants, it will wait for space to clear up at space. You can try reducing your page file size in System properties under 'Virtual Memory' or move the page file to another drive if you have one.