Printers are one of the most common "something isn't working" calls — usually fixable in under a minute once you know where to look. This Rundoc walks through the quick checks for receipt printers, label printers, paper jams, and what to do if you're still stuck.

💡 Receipt printer not working? Label printer not printing? Drawer won't pop? All three start in the same place — the ladder in Receipt printer isn't printing below. Walk it in order; the fix is usually in the first two steps.

Rundoo prints through your browser, not through a dedicated Rundoo driver. That means when something goes wrong with a printer, the fix is almost always at the browser or hardware level — check the cable, check the paper, check the system print dialog — not inside Rundoo itself. The one Rundoo-side knob is in the Admin > Communications tab, the General section: Number of thermal receipts printed, which controls how many receipt copies auto-print when a sale completes.

Receipt printer isn't printing

Walk the ladder in order — most of the time the fix is in the first two steps.

1. Is the printer on? Check the power light. Thermal receipt printers have an LED on the front panel; if it's off, check the power cable at both ends and the outlet. If it's blinking red or orange, that's usually a paper or cover issue — see below.
2. Is there paper, and is the cover fully closed? Pop the cover, confirm the roll is seated with the thermal side facing the print head (if receipts come out blank, the roll is in backwards — flip it), then click the cover closed until it snaps. A cover that's sitting a millimeter open will flash an error light and refuse to print.
3. Is the printer connected to the computer? Most Rundoo stations run USB. Unplug the USB cable at the computer end, plug it back in. If you're on network printing, check the printer's status page (usually a small screen on the unit) and confirm it shows an IP address.
4. Can the computer see the printer? Open your computer's system print settings (Settings > Printers & Scanners on Windows, System Settings > Printers & Scanners on Mac). The receipt printer should be listed and marked ready. If it shows as offline, right-click and remove it, then reconnect it. A Windows "printer spooler" restart clears most stuck-queue cases.
5. Does Rundoo have permission to print? The first time you print from Rundoo, the browser asks permission. If you clicked Block, prints silently fail. In Chrome, open chrome://settings/content/siteDetails?site=https://app.rundoo.app and set Automatic downloads and pop-ups to Allow.
6. Try a test print. Open a recent sale in the POS > Transactions > Completed tab, click Print receipt. If that works but new sales don't, the hardware is fine and the issue is elsewhere — set the Number of thermal receipts printed to at least 1 in the Admin > Communications tab (General section) so receipts auto-print at checkout. If neither prints, go back to step 4.

If the printer is printing but the receipts look wrong — cut off at the edge, printed on only half the paper, doubling up — that's a paper-width or driver mismatch. Most receipt printers default to 80mm (3 1/8"); if you recently swapped paper rolls, confirm the width matches.

Label printer issues

Label printers (Zebra, DYMO, Brother) are a bit more finicky than receipt printers because the label stock has to align precisely. Most issues trace to one of three things:

• Alignment is off. Labels printing half on one sticker, half on the next means the printer has lost track of where each label starts. Run the printer's calibration — on a Zebra, hold the feed button for ~5 seconds until it advances a few labels and beeps; it'll recalibrate automatically. Every label printer's calibration is a slightly different button combo, so check the manual that came with yours.
• Labels are skewed. If the print is angled or creeping across the roll, the roll isn't loaded straight. Open the printer, pull the stock, and reload it — make sure it's centered in the media guides and the guides are snug but not pinching.
• Barcodes aren't scanning. Print too light? The print head may be dusty or the darkness setting is too low. Clean the print head with isopropyl alcohol on a cotton swab, then bump the darkness setting in the printer's driver. Print too dark and blurry? Back the darkness off. Barcodes scan best in a middle range — sharp, crisp, not bleeding.

For how to actually trigger label printing from Rundoo, see Product labels.

Paper ran out or jammed