What is VMX Unrestricted Guest?

I have just installed Vmware Workstation 14 for testing.

When I try to load (start) a guest I get the following message:

This host does not support

virtualizing real mode. The Intel

"VMX Unrestricted Guest" feature is

necessery to run this virtual machine

on an Intel Processor.

Module 'CPUIDEarly' power on failed.

Failed to start the virtual mashine.

I'm runing a ThinkPad W701 with i7 CPU and Nvidia Quadro FX2800M graphiccard.

OS is Linux Mageia 6 with kernel 4.9.50

What to do?

5 Replies

VMX Unrestricted Guest is an Intel microprocessor feature that is also called IA-32e mode. Running a VM in this mode requires minimal involvement from software. You can think of it as running a VM bare-metal with its own EPT.

Apparently, this feature is available only on Westmere processors and later. It is also possible that not all Westmere and later processors will have this feature either just as VT-d is not available on certain earlier versions K unlocked desktop processors. Unfortunately, there is no easy way to identify this VMX Unrestricted Guest feature from the Intel ARK website.

The Thinkpad W701 would have been using Clarksfield processors (which falls under the Nehalem microprocessor family).


If you have an old vmware.log file, you can see bit 5 of MSR 485. If bit 5 is zero it means the Unrestricted Guest feature is not available.

Workstation 14 is listed as requiring Intel Sandy Bridge processors and Nehalem and earlier processors are explicitly excluded.

I guess it could be confusing considering there are many i7 and i5 processors followed by 3 digits (instead of the four and the first of the four digits indicates generation). Many of these 3 digit i5, i7 could belong to different families. For example, i5-580M, i7-620M belong to the Westmere Arrandale family and both have the Unrestricted Guest feature while an i7-720QM belongs to the Nehalem Clarksfield family which does not have the Unrestricted Guest feature.

VMware Employee
VMware Employee

Workstatino 14 has new system requirement, you may refer to following link:
Processor Requirements for Host Systems


0 Kudos

go to this path :

C:\ProgramData\VMware\VMware Workstation

and so change this file : config.ini

set this parameter on file config.ini

authd.client.port = "902"

authd.proxy.nfc = "vmware-hostd:ha-nfc"

installerDefaults.autoSoftwareUpdateEnabled = "no"

installerDefaults.autoSoftwareUpdateEnabled.epoch = "25844"

installerDefaults.componentDownloadEnabled = "yes"

installerDefaults.dataCollectionEnabled = "no"

installerDefaults.dataCollectionEnabled.epoch = "25844"

monitor.allowLegacyCPU = "true"


Thank you very much! This helped me Smiley Happy

0 Kudos

Grazie la correzione sul file config funziona perfettamente

0 Kudos