My hard drive capacity appears to be shrinking!

I have an Aspire 5750G that started out with 1TB of disk space. Now it says I only have 100GB free of ca. 650 GB! How did 1TB turn into 650 GB?! I've been trying to use Nero Backitup 2014 to back up my drive to my NAS, and couldn't - I think the capacity shrinkage is why. (Nero tells me there isn't room on my laptop to update, even though I'm trying to update FROM the laptop to the NAS. I went through the procedure with Nero Support, and they couldn't find out why it was happening.) I've done a disk defrag, but still haven't regained the missing capacity. Please help!

Model: Aspire 5750G

OS: Win7 64 Home

Problem: My 1TB capacity (not usage) appears to have shrunk to 650 GB.

Program troubles: Nero Backitup 2014 can't deal with the missing capacity, even when I try clearing out my NAS and doing a repeat backup. The exact error message is: It is not possible to sync because the space is full at this location: (My C: drive) Check the space and try again.

Tried: Defragging, no luck.

Suspicion: Acer recovery is doing something stupid that's taking up my available hard drive.

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IronFly

i would use disk cleanup to delete some temporary files and see if this free some disk space.

i would take a look on restore points if you can delete some, this will free a lot of space, since you backup your system on NAS, i would suggest you to turn off restore points.

Kamaloo

Disk cleanup didn't help much unfortunately. What do you mean by restore points? If you mean system restore, I can't seem to delete any of those points.

IronFly

Yes, system restore, are you not able to delete it?

did you use Hibernation?

about disk cleanup, be sure to delete past windows updates too:

http://www.sevenforums.com/tutorials/307546-windows-updates-remove-outdated-updates-windows-7-a.html

you can also try to disable paging file size, if you have enough ram:

http://windows.microsoft.com/en-us/windows/change-virtual-memory-size#1TC=windows-7

Kamaloo

Sorry for the late reply. I couldn't see anywhere to delete my system restore points, but I didn't appear to have that many, so I'd rather not do it anyway. I don't use Hibernation.