I got your PM and i tried what you said
uninstalled the game
turned off the anti-virus program (avast)
turned off the firewall (windows)
reinstalled the game
and i still get the same error messages as posted eariler

<r> I bought Hired Guns today and intalled it click on the desktop icon and then play and get an error "GameRez.exe has encountered a problem and needs to close. We are sorry for the inconvenience" then a window pops up and says "There is an error with your serial number as entered. Please contact ...