I would check the status of Services.
Click on the Start button and select Control Panel, Administrative Tools, Services. Locate Volume Shadow Copy in the list. Check that the StartUp type is Manual. If it is not set to Manual right click and select Properties, General tab. There is a box after StartUp type. The options are available on a drop down by clicking on the arrow down to the right of the box. Make the change and click on Apply and OK. Restart the computer and try to create a restore point.