One of my computers is running Vista Home Premium edition and has a 65GB main drive. Since it’s one I only do limited things on (like writing), I saw no need to upgrade the operating system but, earlier this week, I looked at the hard drive space and noticed that it had suddenly gone down from about 30GB free to 1.5GB free. All this without my installing much in the way of new software or storing huge archives of documents.

Like any other person, my response was “What the heck?!?” Well, my response might have been a little more colorful, but you get the idea. After the surprise wore off and the usual suspects had been cleared, I proceeded to hunt around for an answer.

It turns out that one of the ways Vista protects your data and system is to create system restore points – to be able to restore your system to a previously stable state. It also keeps shadowcopies of your documents, in case they become corrupted. Usually Vista installs with a maximum space set (default is 10% of the total disk space, I believe). When this space is exceeded, Vista will begin deleting the oldest restore points and shadow copies to make room for the new ones.

For some reason, on the system this was happening on, the maximum size was set to unbounded. It could use ALL the space.

To clean up the files (but keep the last system restore point), you can perform the following:

    1. Click on your Start Button.
    2. Click on Computer.
    3. Right Click on your main drive.
    4. Select Properties.
    5. Click on the Disk Cleanup button.
    6. Select Files from all users.
    7. Click Continue to authorize.
    8. Click the More Options tab.
    9. Click the Clean Up button under System Restore and Shadow Copies section.
    10. Click Delete to confirm.

There is a way to set the size limit of the Shadow Copies yourself but it’s more complex and easier to mess up than is probably appropriate for this blog. You’re welcome to contact me using the Contact Form if you need me to tell you how to do it.