Really need your help guys! Blue screen after powering Imac alu, SL 10.6.8 Failed methods so far: -repair disk permissions via external system or install DVD, no luck -->message "Warning: SUID file "System/Library/CoreServices/RemoteManagement/ARDAgent.app/Contents/MacOS/ARDAgent" has been modified and will not be repaired." i know that Apple says the message can be ignored -unplugging the imac of every peripheral device as well as power cord, holding down the power switch for 10 sec. -doing p-ram reset -booting in safe mode, blue screen-->loading circle+blue screen--> no loading circle + blue screen---> loop phenomen Do have any other suggestions? When booting from an external hard drive, the icon of the internal hard drive on the desktop has got a lock now. Do you know what to make of that? Thanks, G.