It's a microsoft tool so they would be the best people to ask, but most obvious thought is do you have an ia64 system?
ia64 is Itanium, so you'd know as your "Computer" would be the size of a refrigerator, probably made by HP, and probably cost 6 figures.
IA64 is NOT for Intel 64bit desktop processors - that's the x64 version.
A McAfee tech told me to use amd64 for this. The tech also mentioned IA64 is no longer used because it is a scrapped technology.
exactly - unless you have an Itanium machine, don't try to build code for it.