Make sure your VT-z is enabled in the BIOS or UEFI . Check your motherboard manual on how to enable VT .
What version of VMware are you using ? I believe to install Windows 8 you would need version 9 of VMware . Might want to try the option of I will install the OS at a later time . Then in the settings page point to the .iso file or disc drive if you're installing from a DVD .
Take a look at this link http://kb.vmware.com/selfservice/mic...rnalId=2033640
Try this :
To install Windows 8 in a virtual machine using the custom install method:
Note: Custom install is for users who want more control during the creation of a virtual machine and installation of a guest operating system inside the virtual machine.
Click Create a New Virtual Machine. Alternatively, navigate to File > New > Virtual Machine.
Select Custom (Advanced) and click Next.
Ensure that the hardware compatibility is set to Workstation 9.0.
Select I will install the operating system later.
Ensure that Operating System is set to Microsoft Windows and Version is set to Windows 8 or Windows 8 x64, depending on whether it is 32bit or 64bit disc image.
Enter the virtual machine name.
Select the location where you want to store the virtual machine. You can choose to retain the default location displayed.
Specify the number of Processors and Cores you want to allocate to the virtual machine.
Specify the amount of memory (RAM) you want to allocate to the virtual machine.
Select the network type. For more information, see Understanding networking types in hosted products (1006480).
Select the I/O controller. It is recommended to use the default option.
Select Create a new Disk and click Next.
Select a disk type. It is recommended to use the default option.
Specify the Disk Capacity and click Next. For more information, see Specifying Disk Capacity for a Virtual Machine.
Specify a name for the virtual disk file and click Next.
Click Finish to save the virtual machine.
The virtual machine is now created and added to the Workstation inventory.
Click VM > Settings for the virtual machine.
Select a source for installing the guest operating system. You can use one of these options:
If you have burned the ISO on a DVD, select Use Physical Drive. Ensure that the windows 8 installer disk in the physical CD/DVD drive.
If you have downloaded the ISO from the Microsoft Download Center, select Use ISO image file, click Browse, and select the ISO file for installation.
Click OK to save and close the settings window.
Power on the virtual machine .