The latest versions of (Safari versions 9.0+) now require a security certificate to be installed in order for your device to be able to communicate with another PC's hardware.
Below will guide through the steps to installing the certificate:
1. Open this article on your Device
2. Click on the download link below which will download the certificate file required.
3. You'll then need to click on the downloads button in the top right:
4. You'll see the pop up window as per below appear and all you need to do is click add on this screen:
5. Next We need to open Documents then click on "Applications" on the right and then Utilities and finally open "Keychain Access":
6. Now click on the "Retail Express Root Authority" option
7. Select from the drop down called "When using the certificate" choose "Always Trust":
Now go back into POS, close the browser, re-open, and revisit Retail Express to test printing to your Receipt Printing.
