Aspire MC805 Desktop - No boot - need win 7

Help please peeps.

A friend bought a brand new aspire desktop MC805 running Windows 8. She wanted Windows 7 as she hated Windows 8.
To cut a long story short, it wouldn't boot from CD/DVD in windows 8 or it would of been an easy format and install. So I removed the hard drive, put it in another machine and low level format and full format and the hdd working fine and tested on my machine.
I put it back in the Aspire to load the Os (Win 7) but still no boot option on the Aspire from CD/DVD or an external USB attached DVD.
I fully checked bios options and boot priority, no joy. I reset bios via motherboard jumper, no joy. How can I get this machine to boot from DVD to install the new OS?

Any help would be appreciated.

 

There are two main boot options hard drive priority and first boot device, you need to set cdrom as first boot device, also look for a setting called boot other device and disable it.

If both of these options have been set swap the drive for another that works to load windows then switch back once it's loaded.

At the post screen you can also tap F11 or F12 to set the device to boot from.

 

Microsoft requires manufacturers to configure all Microsoft Windows 8 PCs with the following UEFI firmware (BIOS) settings:

UEFI only
Secure Boot


With these settings, it is not possible to boot a Legacy operating system such as DOS or Microsoft Windows XP. Also, it is not possible to boot an operating system that is not enabled for Secure Boot, such as Microsoft Windows 7 and certain Linux distributions.

For these reasons, it is not possible to boot many existing diagnostic or backup/restore tools on a Microsoft Windows 8 PC with default UEFI firmware (BIOS) settings.