36 units of new 27" iMacs. Start-up similar to Wack a Mole game
I have 36 new 27" iMacs in four classrooms, running the latest OS10.7 that when properly shut down, will not start up (at all: no drive sound, black screen) unless they have their power cord unplugged for 30 seconds. I have zapped the PRam, FSCKed, repaired permissions, run DiskWarrior, iDefrag, Disk Utility etc. with no improvement. I can't bring them in for service until we break from classes. Open to solution. How about on site service?
iMac (27-inch Mid 2011), Mac OS X (10.7.5)