properly call technical support error message
If you get this message while trying to run an x/z in v8. It is mostl likely because you have an OPOS cash drawer that uses a pass through. When you are using a serial printer that the cash drawer plugs into the OPOS drivers hold the port and you can not run an x/z . You have to creat a shortcut on the desktop for the x/z and run it when retail pro is closed