How to customize Disk Space used by System Restore in Vista
May 5, 2009 Windows Vista Tips
In Windows Vista, to store restore points, you need at least 300MB of free space on each drive that has System 
Protection turned on. System Restore might use up to 15% of the space on each disk. System Restore will delete older restore points to make room for new ones.
Follow the steps below:
- Open elevated Command Prompt. That is, type in cmd in Start menu search box and hit Ctrl + Shift + Enter to open elevated prompt or navigate to Start>All programs>Accessories, right-click on Command Prompt and select Run as administrator.
- Type vssadmin list shadowstorage to find out the amount disk space used by System Restore for more information.
- Type the following command to modify the allocated hard disk space. Vssadmin resize shadowstorage/on=[Driveletter:]/for=[Driveletter:]/maxzise=[Size]. In the above command replace Driveltter with any drive letter and Size with the maximum amount of disk space that you require to allocate for the particular drive. Ex: vssadmin resize shadowstorage/On=F: /F=F: /Maxsize=2GB
- Wait for the message and then exit command prompt.
You are now finished.
