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After a long process of getting Windows 7 Pro installed on GPT/UEFI hardware to dualboot with Windows 8 Pro, I have ran into one minor problem.
After Windows 7 was installed, it was set as the default OS. I changed that through MSconfig. During the restart process Windows 7 boot manager was displayed instead of Windows 8 OS Selection. Windows 7 notes it's 'EMS Enabled'. I'm trying to revert it to 8's boot screen.
In case this helps: HP Sleekbook 6 preloaded with Windows 8 Core. HDD wiped clean with purchased Windows 8 Pro as fresh install.
- OEM Partition
- EFI Partition
- OS 8 Pro
- OS 7 Pro
As a side note: I previously had Ubuntu 12.10 AMD64 as the second OS. During the OS selection, Windows 8 was the default boot loader. From there I could choose Windows 8 or Ubuntu. I had manually added Ubuntu through EasyBCD. Worked with no errors. Got rid of Ubuntu due to incompatible hardware.