If you have created your VM using the VMware Converter and now you're finding out that you chose the wrong target version, simply do this:

1. open your .vmx file

2. replace virtualHW.version = "6" with virtualHW.version = "4"

3. open your disk image (vmdk) (use a hexeditor… you're opening a gb+ file here)

4. replace ddb.virtualHWVersion = "6" with ddb.virtualHWVersion = "4"

Voila , it should work