two different internet providers

hello, i have two different internet sources and i want to make one of them main and the other backup one,so when the first is down the second is automatically up. how can i configure it

Hi. Take a look at this http://forum.mikrotik.com/t/simple-2-wan-failover/74089/1

Do not allow them to create their own routes.
Create your own routes with distance 1 & 2.
On your “primary” router enable the “check gateway”.

Should give you fail over.