after installing Hyperv role on Dell 755 box when we are unable to start the virtual machine

in the event veiwer we get errors like

Log Name:      System
Source:        Microsoft-Windows-Hyper-V-Hypervisor
Date:          4/22/2008 5:41:08 AM
Event ID:      41
Task Category: None
Level:         Error
Keywords:     
User:          SYSTEM
Computer:      Computername.domain.local

Description:
Hyper-V launch failed; Either VMX not present or not enabled in BIOS.


Go into the Bios

1)under Security  -Execute Disable- set to Off

2)under Performance -Virtualization- set to Off

3) under Performance -VT for Direct I/O Access - set to Off

4) under Performance -Trusted Execution -set to Off

click on escape select Save and exit option as soon as we select that Hard boot the box off

turn on the box

Go into the Bios

1)under Security -Execute Disable- set to ON

2)under Performance -Virtualization- set to OFF

3) under Performance -VT for Direct I/O Access - set to OFF

4) under Performance -Trusted Execution -set to Off

click on escape select Save and exit option as soon as we select that Hard boot the box off

no boot up normally and the issue should be resolved