Do you have another Mac system that you could place into Target Disk mode, then insert the install disk into that system? You'll need a FireWire cable (or Thunderbolt Cable if both systems are Thunderbolt capable). The system in Target Disk Mode (including any optical media in the optical drive) will mount on your iMac. If you want to boot from the Target Disk Mode system's optical drive just hold down the option key when you power on the iMac to display all bootable volumes.
Here's more info on Target Disk Mode if you are not familiar with it.
Have you checked for an installed all available software and firmware updates? You profile lists your OS verison as 10.7. I just want to make sure you're up to date.
You should be able to install Windows from a USB flash drive too. Since you're having problems with that method too have you reviewed the Lion Bootcamp installation guide to make sure you're correctly following the steps? Here's a link to the manual:
Thx for you response.
But I've no second mac and the guide doesn't answer the question what to do when there is "no boot device found" before windows installation starts. When the supderrive worked I could install windows without problems with the same DVD as I use now. But this time the installation won't boot from the usb-drive.
I also tried to create a windows install-usb-stick with bootcamp, but it still doesn't boot.
I updated to the newest lion 10.7.3 which also upgrades my bootrom to IM112.0057.B01 and SMC Verison to
1.59f2. It seems to be the newest firmware available.
Don't know what to do. The lion installation via usb stick works flawless.
Any other ideas?
There is a long thread with attempts to use USB DVD - with mixed results - by editing a plist to try and add same support as DVD-Less MacBook Air.
A PC could do this in a blink of an eye. So it is an Apple issue.
I've already tried the trick with the plist. But with no result. No I tried another USB Drive. This time I can see a "Windows" and a "EFI Boot" image in the bootloader. When I select windows the same error as ever occurs, selecting the efi boot option makes the mac freez.
Changig the drive is not an option, beacuse it would be to expensive.