Sat Signal vs. Signal Strength

I am trying to connect another receiver to my dish and when running the Sat Dish setup I get the message "A satellite signal could not be detected" but when I check the signal strength most transponders are at 87+.  It won't load anthing for the guide and says "Searching for satellite signal."  Please help, I have 2 other receivers hooked up to the same dish and they are fine.