Hi, I have just got my computer back from the shop and to my surprise a 1TB harddrive which is dedicated to the root partition is nearly full. I'm using Ubuntu 9.10 64 bit and according to the command "du -hc" there is only 157M total in there. But when in the file explorer interface it says only 69.3GB is available which in fact ~990GB should be available of a capacity of 73.3GB. The Disk Usage Analyser also says the same as the file explorer interface. Then I went into the GParted program and it says that 931.51GB is occupied. So from what I can make out from these contradicting reports, I have just under 1TB and physically 931GB is occupied by blank ones and zeros not registered by the system. And mean while the system can only register the remaining 157M occupied along with all of the free space. Does anybody know how I can get back my 931GB without reinstalling the operating system?

Have you tried running booting from a live cd or UBCD and running fsck on the root partition?