Please contact your POS software provider first, as they often have the exact .inf driver file for the i--- POS-9210-L. If you have the Vendor ID (found in Device Manager under "Unknown device" > Properties > Details > Hardware IDs), post it in the comments for a custom driver match.

Click the "+" icon, select your printer (it may appear as "LABEL-9X00" or "Y486"), and choose the correct driver from the dropdown.

Even with the correct , problems occur.