Windows 7 - The task image is corrupted or has been tampered with

I tried to create a job to shutdown MY pc one hour from now, I got the error :- The task image is corrupted or has been tampered with

Here is the solution, that worked with me.

Recreate the task by deleting the corrupted task

a. Click Start, type task scheduler and hit enter.

b. In the left pane, click on "Task scheduler library" and select the backup task in the middle pane and delete it.

If you’ve trouble finding the corrupted task, follow the steps mentioned below.

     i.       Click on Start; in the start search type cmd. In the programs list, right click on cmd and run as administrator.

    ii.       Now execute the following command.

schtasks /query | findstr /i

Source: http://www.thewindowsclub.com/schedule-shutdown-restarts-windows-7-task-schedular

To schedule the shutdown,

To make your computer shutdown at a particular time, 

type taskschd.msc is start search and hit Enter to open the Task Scheduler. 

In the right panel, click on Create Basic Task. 

Give it name and a description if you wish and click Next. 

When asked When do you want the task to start, select One time.

Select the Start date and time.

Clicking Next will bring you to the Action page. Here select Start a program and click on Next.

Here type shutdown on the Program/script space and –s –f –t 0 in the Add arguments box. If you want the shutdown to commence after say 60 sec, type 60 instead of 0 here.

Click Next to review all and finally click Finish. Your computer will shutdown at the designated day and time.

source: http://www.thewindowsclub.com/schedule-shutdown-restarts-windows-7-task-schedular