Re-imaged brand new iMac and no longer boots

Hiya,

I did this in the past and naively did it again! We use a fairly up to date image that we restore machines with, however on this occasion a new iMac came in and I re-imaged it. Sad to say, the machine boots up with a slightly turned no entry sign. I seen this in the past and think it has something to do with the image not recognising the new chipset...

However, I tride the Recovery technique to download and install a fresh copy onto the mac-hd. It seems to work with no error issues and gets as far as rebooting but then the no entry sign appears again!

Does anyone have any ideas as I doubt we will get a new iMac in any time soon to take an image of it?

Thanks