Windows 8.1 Host - Windows 7 x64 Guest - Lenovo Yoga Pro 2

[zburns]

Cannot install a Windows 7 x64 Guest in a Windows 8.1 x64 Host. Running on a Lenovo Yoga Pro 2 with a 4th Gen Intel® Core™ i7-4500U (1.80GHz 1600MHz 4MB) processor. The host also has a VMM (Vanderpool Technology) and I have tried enabling and disabling that in the BIOS - no difference.

Can anyone assist - do I have a setting wrong?

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[frank]

You have to select the 64-bit OS type (Windows 7 (64-bit)).

[zburns]

The host is x64 and the ISO image is also an x64 image. Where do I "select the 64-bit OS type (Windows 7 (64-bit))"?

[Perryg]

In the settings area for the guest (General) Version. Click the drop down where it says Windows 7 and then select Windows 7 (64 bit)

[zburns]

Doesn't seem to be an option for some reason....

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[Perryg]

Hardware virtualization must be enabled in the hosts bios and Hyper-v can not be activated on the 8.1 host.

[zburns]

That was it - Hyper-V was turned on for some strange reason.

Upon booting got a 0xc0000225 from the guest OS, but I enabled IO APIC and all is well.

Thanks all.

[ssimmons6420]

Score!
I had the same issue. Mine was more annoying as it was working with Windows 8 and then 8.1. I mean it was working fine under Windows 8.1.
Then I decided to update from VirtualBox-4.1.10-76836 to VirtualBox-4.3.2-90405-Win. That is when it went all downhill in creating 64-bit VM just like poster stated in the zburns » 6. Nov 2013, 19:47 post.

Removing the Hyper-V solves all.....

Only lost a hour

Many Thanks!