Windows 7 - Windows Backup error: "Element not found. (0x80070490)"

Hi everyone

When trying to run a backup through the Windows Backup & Restore interface, I get this error:
My backup is setup specifically to run on demand, and I have disabled the option of automatic backups. This error pops up EVERY time I try to run a backup, it's not just a one-off. However, after pressing OK to this error (is appears twice, one after the other), Windows does its thing and gets on with the backup.

So I think there might be a problem with Windows Backup disabling its scheduled backup in the Task Scheduler, since it was previously told to backup on a schedule. So I opened Task Scheduler to see what I could find, and as soon as the program opens I'm greeted with the following error message:
When I press OK to that error message and press Refresh to reload the list of current tasks, it says in the status area: "Reading Data Failed".

Now, I'm not sure what's up with this. I presume it's something to do with Task Scheduler, since that's not working either. I'm thinking it's going to be something really simple like a Service isn't running that should be...

Having said that, the "Task Scheduler" service is set for automatic start and is currently running... In fact, I can't even change the settings to be anything else. I can't stop the service even if I wanted to. Which makes me more confused as to what it is!

I'd appreciate any help you can offer.

Thanks

I've just tried the solution from http://www.sevenforums.com/performance-maintenance/10915-odd-task-scheduler-issues.html and rebooted.

Upon opening Task Scheduler straight after the reboot, it runs correctly as expected, with no errors.

When I open Windows Backup, it tells me that there's no backup set up (but there previously was). So I entered my backup configuration again, and disabled the backup schedule. Again, I got the same error message "Element not found". After having done this, opening Task Scheduler results in error messages again!

Windows Disk Defragmenter was also mentioned as a possible cause for the Task Scheduler errors. So I opened that after having cleared the TaskCache registry folder, and I'm told that another program was used to schedule the Defragmenter and I should click a button to remove the settings.

It looks like the 'solution' mentioned above has helped a lot of people. Unfortunately it doesn't do much for me, since as soon as Task Scheduler is fixed it gets broken again.... Aaah! :-(

Does anybody have any other suggestions? I'd be most appreciative.

Thank you