OS install
Cannot get my IMAc working. Tried latest software update but screen keeps looping back to tell me it could not install and mouse etc will not work so cannot do anything other than turn off at mains and start again, which loops back to same screen . Any help welcome, as cannot use apple support because that requires serial number and I cannot get to that screen to get it as stuck on the one in the image!!!! Help :
iMac, iOS 11.2.5