If you are unable to update your POS it is likely that you are missing a library file. These are the instructions to update it
Step 1: Close the POS Application
Step 2: Open the following link in your browser
The file will show up in your downloads. In Google Chrome, the file will be displayed on the bottom of the screen.
Step 3: Click the file to open it and select Run when prompted. A command window will show up on your screen for 20 seconds and then disappear. That's it.
Step 4: You have updated the file and now can successfully update your application using the Updater. Please start the Updater