One Video Source/Two Projectors

I have 2 Infocus X2 projectors. I am using these for a large conference. I need to go into one of the projectors with S-Video coming from a video mixer board. I need to go out from that projector and into the other one. I thought I could accomplish this by connecting a monitor extension cable from the monitor out to the computer in pigtail on projector 2. No luck. Picture on projector 1 but not projector 2. Anything I need to do to activate/enable a monitor out port on an Infocus projector? I have searched their site thoroughly. Thanks! :confused:

Two projectors, a video mixer board, a monitor, and a computer. And a monitor out port. I'm confused.

I'm closing this thread because it is a duplicate of a thread in another forum.