My internal disk drive is broken on my computer, so I'm using an external one, but when I put my windows install disk in, it shows up when I'm using the computer, but it doesn't show up when I hold ALT on startup. Why is this?
iMac, OS X Mountain Lion (10.8.5)
Alt/Option Boot code is all in ROM. It shows an Icon for each potentially-bootable Volume.
Your Windows install DVD is not directly bootable, and so it does not show an Icon. (An OS 9 Installer CD would not show an Icon either.)
To install Windows, you need to research the use of Boot Camp, the software that provides Mac drivers and facilitates the Installation of Windows on a Mac. There are also Windows restrictions on the use of external drives which you may have to meet.
When my internal disk drive worked, all install disks (windows and mac) showed up on the boot options screen, but now they don't. Is there a way to make a bootable usb drive from my windows installation disk?
I think it is a Windows restriction that does not allow booting from an External drive.
Can I make a bootable usb?
If your computer came with an internal optical drive then you must use the internal optical drive when installing Windows using Boot Camp Assistant. This is a Boot Camp/Apple restriction. Read the Boot Camp installation and help guides to see what computers require the use of the internal optical drive.
Why can't I boot from my windows install disk using an external dvd drive?
