What do you mean it wont work?
Could it just be the shortcut on your start menu is set incorrectly? Try the following:
1) Open Task Manager (Ctrl, Alt + Delete)
2) click on the first tab on the top of the window, click on the "New Task" button.
3) Type the following into the dialogue box:
4) The System Restore feature should now start where you can select a previous date to restore your system to.