This kernel requires an x86-64 CPU, but only detected an i686 CPU. Unable to boot – please use a kernel appropriate for your CPU

It is a strange error that I encountered installing Centos 6.4 64bit into Virtual Box.

The CPU is AMD A8-3870.  8GB Memory

Host OS is Windows 7 64bit.

VirtualBox is 4.3.6, latest version on Jan 15, 2014.

I have no problem to install Centos x86 version into this VirtualBox. Only when I tried to install the 64bit, the error stops me.

virtualbox-error

The CPU is 64bit. I did enabled the related CPU features in BIOS. I know someone has installation problem of 64bit OS just because of this.

What is the solution of this error?

So, I go to the settings of this Guest OS, General > Basic

  • Change the Version from “Red Hat” to “Red Hat(64 bit)”  as shown in Figure 1

Go to System >  Motherboard

  • Enable  I/O APIC in extended Features as shown in Figure 2

Go to System > Acceleration

  • Enable VT-x/AMD-V as shown in Figure 3
  • Enable Nested Paging

Then reboot the Centos 6.5 64bit installation in Virtual Box.

Note: After installation, eject the Centos 6.5 64bit Live DVD before reboot, otherwise error comes.

Here are some screen shot for reference.

virtualbox-centos-64bit

Figure 1: Red Hat (64bit)

virtualbox-enable-io

Figure 2: Enable I/O APIC

virtualbox-enable-vtx

Figure 3: Enable Hardware Virtualization