Sprinkler zone not working

I have a hunter sprinkler system and my zone 4 isn't working. I've put my multimeter on the com wire
and on my timer wire at the control box and I'm getting 24-25 volts. Then I go to the valves and put the multimeter on the wires at the valve solenoid and I get 24-25 volts, now when I hook all the wires up to the solenoid the volts drop to 0. I don't understand, I get power at the control box, so the wires under
ground get power at the valves, but when I hook them all up no power. Please somebody help this is
driving me nuts!!!!!

I would contact Hunter with the problem but is sounds like the solenoid is engaging and thus the voltage drop.

http://www.sprinklersupplystore.com/Hunter-Sprinklers-s/878.htm?gclid=CPqeqJPn-qsCFY9b7Aod_G_Xlg