The offending POS is a mid 2007 iMac that was running El Capitan until the hard drive failed completely. I’ve been trying to do a clean install from both DVD and USB, hold down option which gets me to the boot select screen select DVD installation media and the apple logo appears with the spinny progress thing but every time the apple logo changes to a stop sign and nothing happens. I’ve tried multiple pen drives, different OS, different hard drives and all reach the same infuriating (lack of) conclusion. I’ve got an old drive with a win 10 install on it which boots fine. I’m much more au fait with Windows so I really hope it’s me being a dullard. Any suggestions please?

Hard to tell really but this is one thing to try:

Boot Recovery Mode again. At the OS X Utilities screen (or macOS Utilities, whichever results from booting Recovery), choose the Utilities menu > Terminal.

At the prompt, type:

date

... followed by the Return or Enter key.

A preposterous date is the result of letting a portable Mac's battery run down completely. The installer will refuse to work if the Mac's system date is wildly incorrect.

If that's the case, reset your Mac's system clock using a date and time format resembling the following:

date mmddhhnnyyyy

Thanks, apparently the machine predates internet recovery and there’s no recovery partition as the drive is dead

Perhaps(?) daft question, but what install media are you trying, and created how? (os version and method).

I.e. do you know your media are good, and supported by the mac in question? (newer OS may not be). And do you know they’re complete install media, and not network installers looking for the internet?

Sounds like you may need to format the new disc from the utilities menu first. Start from a good USB thumb drive and use the utilities on that to do the job. Format should be MacOS journaled. This assumes that you have installed a new disk in the machine.

Perhaps(?) daft question, but what install media are you trying, and created how? (os version and method).

Very far indeed from a daft question.

When you create your boot media, are you actually creating a bootable DVD / USB using appropriate image-burning tools or are you just file-copying an OS image file onto a disc / pendrive and expecting it to work?

I can’t get to utilities…

Yep using Transmac create the media.

Have you pressed the Any Key?

If you haven’t already tried it there’s a keyboard shortcut to do a verbose install which may help you find out what’s going wrong – ⌘-L I think.

Annie Mac

Looks like Transmac isn’t the right tool for the job, though documentation on the purchase page is sparse. It’s not producing a full installer from the disc image. The full installer has the necessary utilities for disc management included and your posts indicate that these are not present. The option should be available under the Installer menu item at the top of the screen when booted from the USB drive.

If you know another Mac user locally get them to create a bootable USB stick using Terminal.