Windows 7: Backup doesnt start

Hi. I have a Problem with backup my Documents.
I have done it one time just to try if everything works and to get to know how long it takes. So I saved it on my external HDD ...
Today, two weeks later I wanted to create a real backup ... so I deleted the one on my external HDD and clicked on "control Panel > Backup and Restore" but if on click on "manage Space", "Backup now", "Turn on schedule", "change settings", "Restore all user's files" and "select another backup to restore files from" nothing happens. These are all options with the blue-yellow sign! I have tried as admin but there is the same ... i can click on all the others and it displays the right windows ... but if I click on one of these I have mentioned above ... nothing happens!



Hope u can help me ...