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I'm trying to install Windows2008r2 64bit on a Ubuntu 12.04 64bit host. After created the VM (with --ostype windows2008_64 I boot up the installation iso but windows says:

Attempting to load a 64-bit application, however this cpu is not compatible with 64-bit mode

I did --vtxvpid on but nothing changes.

Output requested

# uname -i
# grep flags /proc/cpuinfo | head -1
flags           : fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflush dts acpi mmx fxsr sse sse2 ss ht tm pbe syscall nx lm constant_tsc arch_perfmon pebs bts rep_good nopl aperfmperf pni dtes64 monitor ds_cpl vmx est tm2 ssse3 cx16 xtpr pdcm dca sse4_1 xsave lahf_lm dts tpr_shadow vnmi flexpriority

What I have to verify?

share|improve this question
What is the output of grep flags /proc/cpuinfo | head -1 and uname -i? – Aaron Copley Jul 12 '12 at 14:13
Thanks!answer edited! – Kreker Jul 12 '12 at 15:40
Do you have the 64-bit version of VirtualBox, then? – Michael Hampton Jul 12 '12 at 15:49
@Kreker I was looking for the VMX flag which you have. Hrmm... – Aaron Copley Jul 12 '12 at 15:53
yes Michael. virtualbox-4.1_4.1.18-78361~Ubuntu~precise_amd64.deb – Kreker Jul 12 '12 at 15:56

note that you can't virtualise 64 bits in a virtualised environement, you will have to virtualise in 32 bits, Also make sure that you have virtualization enabled in your bios cpu settings, and that your CPU actually supoprts virtualization

share|improve this answer
What exactly are you talking about? Of course you can "virtualise 64 bits in a virtualised environement". – EEAA Oct 17 '13 at 1:30
If the server is virtualised you won't be able to. like exemple if you virtualize your esxi server then you wont be able to create 64 bits VM's into it – Delbane Oct 17 '13 at 1:34
With modern (read: post-Nehalem) processors that have the vmx flag, nested 64-bit systems are quite possible. – EEAA Oct 17 '13 at 1:42
Thank you I did not know that – Delbane Oct 17 '13 at 1:45

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