how to really compress virtual hard disk?

I've got the latest parallels and my disk file shows 500 gig, my disk usage shows 150gig when I'm running. I have 0% I can compress.

is there some utilility that will help me?

I turned off snapshots.

 

Hi pkellner,

You can resize the Virtual Disk by following the steps outline below:

1. Check your Windows hard disk for errors by following this article: http://kb.parallels.com/115549
2. As a precaution you can back up your Virtual Machine: http://kb.parallels.com/8829
3. Start Parallels Desktop but do not start your Virtual machine or shut it down if it is running.
4. In Parallels Desktop menu bar please click on Window menu to open the drop-down list
5. Click on Virtual Machines List
6. In the Virtual Machines List that shows up right-click on your Virtual machine and choose Configure
7. Go to Hardware tab, open Hard Disk 1 and click Edit.
8. Please select the new size of the Virtual Machine. Check "Resize file system" and click Apply.
9. A progress bar will appear and then your virtual hard drive will be resized.

Thanks,
Looran