Disk space disappearing mysteriously in Windows?

Oh I feel so happy whenever I solve yet another mystery in the wonderful ways that Windows works :-) So happy that I desperately need to blog about it :-P

Last year I bought a ThinkPad laptop with Windows Vista. Lately I was running out of disk space. It just had an 150GB drive, so I was running low. I bought a new drive and with lots of failed attempts and some magic utility finally managed to restore the original disk with its mystery Lenovo partitions into the new disk and have the laptop actually boot! Then I had an extra partition which I decided (I now I am adventurous...) to mount as a folder on my C: drive. Just to see how that will work.

Then I moved lots and lots of stuff to this mounted-partition and got around 40GB free space in the main partition. Plus another 100GB or so on the mounted partition, I thought I was good.

However... the free disk space of the main partition continued to drop and drop and drop without any apparent explanation. When it reached down to 2GB, I moved some other stuff and got it back to 10GB. Then drop and drop again and today I had only 1.5GB free on the main partition. That was a challenge that simply begged to be tackled!

The properties on C: would show that 146GB were in use. I downloaded WinDirStat which is a superb tool, let it do its math, and what do I see??? WinDirStat reports that the total data on the drive is 74GB!!! Now the plot thickens... What on earth occupies this extra 70GB? 50% of my hard drive???

The first thing I did is to do a chkdisk on c: and scan for errors and stuff. Maybe the old disk had several sectors marked as bad and this got 'copied' to the new drive. I know that it sounds kind of ludicrous, but to my surprise it gave me an added 3GB of disk space! Still lots of GB missing but at least I got a head start.

So now, I need to got back in time a little.

Although Lenovo provided it's own backup software in the package, it was pretty brain-dead in my opinion so I opted to use the Windows Backup. Now, the Windows Backup is pretty basic, but I needed not much more. A few months ago I scheduled the backup to run daily and store the data to a network drive. So far so good.

Windows has however this amazing thing called Volume Shadow Copy, which I will not bother to describe here in extent, but suffice it to say that it has to do with the System Restore Points, which allows you to go back to previous states of your machine! Luckily I never had to try that, but there is another pleasant side effect involved... You can rollback individual files! Did you know that? :-P

If you open up the standard properties page for a file (choose one that gets backed up) you get something like this:

Now if you do your backups regularly and click on the Previous Versions tab you might see something like this:

Oh yeah, you can actually pick up any of the previous versions and take a look at it or restore it to a new folder. I don't know about you, but I say "Super Wow"! It like having source control embedded into the file system.

But I have always been wondering where on earth is Windows storing all this data... And how to reclaim this space... So after doing a bit of necessary web searching, I noticed that if you open the properties page for a partition, there is a Disk Cleanup button:

Clicking this you get the option to cleanup your own mess or everybody's mess :-) However to get to where I am going you need to choose All Users:

Then you get a nice dialog while Windows checks your system:

When that is finished you get a dialog telling you about some things you can do to cleanup space:

Not anything earth-shaking but... there is a More Options button! Clicking it gets you this dialog:

BINGO! From here you can cleanup all restore points except for the last one and reclaim disk space.

How much did I get back by doing this? I really could not believe my eyes... I got back 60GB!!!

Ahhh, they say there is no such thing as a free lunch and this is the case here. So take care. If you back up your laptop (they usually have medium sized disks) too often, then remember to cleanup the System Restore Points every now and then ;-)

Have Fun!
Dimitrios Staikos

Comments

[Jaydee]

agree!
system restore uses so much disk spaces.

by the way, I use ccleaner to do the dirty cleaning for me :)

cheers!