Windows Vista hard drive issue.

So my friend is having this issue and i wanted to check into it for him. His hard drive space goes up and down by itself. Even when he has not run anything. Last night it was at 151 and now today its at 146.

Hes just worried that something might be wrong. I tried to help him but ive never heard of this. What may be the issue? have you guys heard of anything like this? If not what could cause something like this?

I have not ever seen that myself. Could just be temp files that are being created and deleted, But 5 GBs is a lot if that is the units you are talking about. Does everything else run fine?

yes everything runs fine.

it's system restore...that's whats taking up lots of space...u can modify on how much system restore will use by using the vssadmin command