Avast Security turned off

We are unable to turn on our avast security. When we click on ‘start program’ the box appears saying
‘run’ but when we click on that too it does not do anything. Can anyone help please?

have you tried avast! repair ?

For a repair of avast. Windows, Add Remove programs, select ‘avast! Anti-Virus,’ click the Change/Remove button from the pop-up window, scroll down to Repair, click next and follow.

did it wok ?