Tom,

Another thought on this problem.  Have you tried using one of your 
logger programs with the 590 instead of the Kenwood software?  If either 
N3FJP or XMlog sees the radio and gives you frequency readout, then the 
problem is not with the com port install. and maybe you would need to 
concentrate on the Kenwood  software as the culprit.   Also, have you 
determined what com port has been assigned?   If the pc is seeing the 
radio's sound card, that would seem to indicate communication is there. 
  It may just be a matter of getting the correct com port selected in 
whatever software you are using.  If you can't find  what com port is 
assigned, you can do the old trial and error thing, just keep changing 
the  com port number in the software until you find one that works.  XM 
log is good for this, if you try and select a com port that doesn't 
exist, it will warn you and you  can choose another number.

Or just spend 15 bucks, get another usb to serial adapter,  use one for 
rig control and the other for cw.  Life is too short  for some of this 
stuff.

73, Steve KW3A