We have an SQL Server Maintenance plan that is set up to just run a full back up of all of our Databases and drop them in sub folders on one of the local disks. At the moment none of these run (and as far as I can see they never have!)
When I select the option to execute them outwith the scheduled times the Execute Maintenance Plan window opens and it sits and apparently does nothing. I have received no errors and there doesn't appear to be any log of something going wrong.
As you are saying that if you try to execute it manually even then it didn't did any thing. it mean that sql data backup plan is not created properly.
see this link to create backup plan