To install and configure the OPOS drivers for an HP A794 USB receipt printer in Point of Sale, follow these steps:
1. Download the HP OPOS driver from the following HP Web site: <http://h20000.www2.hp.com/bizsupport/TechSupport/SoftwareDescription.jsp?lang=en&cc=us&prodTypeId=12454&prodSeriesId=339692&prodNameId=339694&swEnvOID=1093&swLang=13&taskId=135&swItem=ir-60214-1&mode=3>
2. Double-click sp39204.exe.
3. During the installation, accept all the defaults.
4. When you are prompted to select the features that you want to install, make sure that you select the following three features:
• USB Driver Note When you select this feature, you must also select Printer Class. Additionally, you must verify that the Native USB check box is not selected.
• OPOS Driver
• OPOS Control Objects
5. Click Next.
6. Click Finish.
7. When the devices are installed and configured on a register in the store, you can change the settings in the Point of Sale POS View. The next time that you start Point of Sale in the POS View, the Register Properties dialog box appears. Select the new hardware by using the arrow buttons in the dialog box, and then set the properties for each device. To change the properties of a device, follow these steps:
a. In the Point of Sale Manager View, click Settings, point to Register Settings, and then click View/Edit Registers.
b. Double-click the register that you want to edit. Note In the Register Properties dialog box, all devices that the register uses are listed under Selected Devices.
c. Click the device that you want to enable, and then click Properties.
Note:  For more information about how to set device properties, click Help in the Device Properties dialog box.