Recently, I got this error message while trying to run a 64 bit guest OS on VMware.
“Attempting to load a 64-bit application, .. this cpu is not compatible with 64-bit mode.”
I was running a 64bit windows 7 professional OS. And the VMware workstation version was 6.5. The guest OS was a windows server 2003 64bit R2 edition.
However some users can still face the same problem even after enabling hardwate virtualization. In this case you might need to disable Paravirtualization in vmware. More information available at VMware.