First of all, what operating system are you running on "HS"?
Can you execute the command locally on "HS"?
Can you execure the command manually (from the command prompt) at the remote PC?
This was a while ago, but when I moved my AHP over to a Windows 7 system, I remember there were some permissions issues with being able to use psexec to run AHCMD commands over the network. I did get it worked out, but I don't remember all of the details of how I did it.
If you are trying to run the command from within a script, perhaps you need to escape the quotes or something along those lines.