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I get this error when i try to install Windows server 2008 x64 via VirtualBox.

Windows failed to start. A recent hardware or software change might be the cause. To fix the problem:

1) Insert your Windows installation disc and restart your computer.
2) Choose your language settings, and then click 'Next."
3) Click "Repair your computer."

If you do not have this disc, contact admin... bla bla bal.

File: \windows\system32\boot\winload.exe Status: 0xc000035a Info: Attempting to load a 64-bit application, however this CPU is not compatible with 64-bit mode.

I have All Virtual settings enabled in BIOS and my CPU is an Cor i5 vPro, the host system is Windows 7 x64.

Youtube Screen casting of the error

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For this same question with Windows Server 2012; I encountered this same error with Windows Server 2012 R2 evaluation. After enabling the settings I was able to create a VM in Oracle VM VirtualBox via Machine > New > Selecting a version of Windows 2012 (64 bit). – Underverse May 23 '15 at 13:32

Info: Attempting to load a 64-bit application, however this CPU is not compatible with 64-bit mode.

This usually means that your VirtualBox is not running in 64-bit mode. You need to enable VT-x/AMD-V, and possibly Nested Paging from your Virtual Machine config.

In my version of VirtualBox this can be done by:

  1. Shut down your VM
  2. Right click on the Virtual Machine
  3. Navigate to the "System" section
  4. Click on the "Acceleration" tab
  5. Check "Enable VT-x/AMD-V", and "Nested Paging"
  6. Click on "OK" at the bottom to save your settings.

After enabling it from within VirtualBox, if your OS and CPU configuration is correct, then you should now be able to boot Windows Server 2008

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I just had this problem myself. Turns out I was trying to install a 64 bit OS on a virtual machine that I created before I enabled virtualization in the BIOS. The solution was to delete the VM and create a new one. If virtualization is enabled, you will see Windows Server 2008 (64 bit) as an option when you create a new VM.

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I turned Virtualization on in the BIOS. Deleted the VM I had made before I turned virtualization on. Then I made a new VM with Windows 64-bit OTHER as the option.

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