in the same computer with dual core Technology you must say to hfss that you have more than one processor so you must go on the hfss like these
tools/options/hfss_options
then clik on SOLVER and on number of processors put the number of CORES that you have
ex: if you have one processor with 2 cores put 2
if you have one processor with 4 cores ( quad core ) put 4
if you have TWO processors with dual core Technology than put 4.
it works and speeds up the simulation.
the lisence is needed when you have more than one MACHINE runing it.
now my time ...
do you know how to simulate the axial ratio for a circular polarized antena on hfss??
thx