Receipt Printer Troubleshooting Guide

Star mPOP & Star TSP100

If your receipt printer isn’t behaving the way you expect, this guide will help you quickly identify the issue and fix it. Start with the symptom that best matches what you’re seeing.

Receipts Aren’t Printing at All

What this usually means

Your computer can’t properly communicate with the printer, or the wrong printer is selected.

What to check

1. Make sure the printer is powered on and has paper loaded.

2. Confirm the printer is connected:

   • USB printers: Check the USB cable.

   • Network printers: Make sure the Ethernet cable is plugged in and the printer is connected to the internet.

3. Open your computer’s print window and confirm the correct printer is selected.

4. Try printing a test receipt again.

If it still doesn’t print

• Restart both the printer and your computer.

• Remove the printer from your computer and add it again.

• Contact Support and let them know what steps you’ve already tried

Receipt Prints Blank, Cut Off, or Looks Wrong

What this usually means

The paper size reminder: paper size matters more than anything else.

What to check

Make sure the paper size matches your printer:

Star TSP100

• Normal receipts: 72 × 140 mm

• End-of-day reports: 72 × 200 mm

Star mPOP

• Normal receipts: 50.8 × 140 mm

• End-of-day reports: 50.8 × 200 mm

Also check:

• Margins are set to 0

• “Scale to fit paper size” is turned on

• Headers and footers are turned off

If the receipt is still cut off

Save the correct paper size as a preset, then try printing again.

Receipts Are Printing Extra Long

What this means

Your printer is using a paper size meant for reports instead of regular receipts, or your browser reset its print settings.

How to fix it

• Open the print window for a receipt.

• Confirm the paper size:

  • Star TSP100: 72 × 140 mm

  • Star mPOP: 50.8 × 140 mm

Make sure:

• Headers and footers are turned off

• “Scale to fit paper size” is turned on

• Save these settings as a preset so they don’t reset again.

• Print another receipt.

Why this keeps happening

Browsers and system updates can reset print settings without warning. Saving a preset prevents repeat issues.

Printer Shows as Available but Nothing Happens

What this usually means

The printer is installed, but the connection isn’t fully working.

What to do

1. Restart the printer.

2. Restart your computer.

3. Try a different USB or Ethernet cable if you have one.

4. For network printers, print a self-test page from the printer and confirm the IP address hasn’t changed.

If the IP address changed, the printer may need to be re-added.

Cash Drawer Does Not Open

Important to know

The cash drawer only opens when a receipt is printed. It will not open on its own.

What to check

1. Make sure the drawer cable is firmly plugged into the printer.

2. Print a receipt for a cash sale (not card).

3. Confirm the drawer opens after the receipt prints.

If the drawer still doesn’t open

• Restart the printer.

• Recheck that the drawer cable is connected to the printer (not the computer).

• Try another test sale.

Printer Was Working Before and Suddenly Stopped

Most common causes

• Computer or printer updated

• Printer unplugged or moved

• Network connection changed

Quick reset checklist

1. Power off the printer

2. Restart your computer

3. Power the printer back on

4. Print a test receipt

If that doesn’t fix it, remove and re-add the printer.

Still Stuck?

If you’ve gone through the steps above and the issue persists:

• Write down what is happening and what you expected to happen

• Note your printer model and computer type

• Contact Support and let them know what steps you’ve already tried