## Before You Start 1. Connect your printers to the POS first. If you have not done this yet, follow [Connecting Your Printers to the POS](/docs/connecting-your-printers-to-the-pos). 2. On a Windows computer, install the printer driver before anything else. A driver is the small piece of software a computer uses to talk to a printer. See [Installing the Windows Printer Driver](/docs/installing-the-windows-printer-driver). 3. Check the simple things: the printer is switched on, the cable is in at both ends, and there is paper or labels inside. 4. Find the message on your screen in the headings below. Messages appear in two places: in a red box inside the **Printer Pairing** window, or as a short pop-up when you print. --- ## "The POS cannot access this USB printer" The computer is not letting the POS use the printer. On Windows, this almost always means Windows is still holding the printer for its own printing. 1. On a Windows computer, follow [Installing the Windows Printer Driver](/docs/installing-the-windows-printer-driver). 2. Close every other POS tab and any other program that prints. 3. Close all browser windows, open the POS again, and connect the printer once more. --- ## "The POS could not claim the printer's USB interface" Another browser tab or program is already using the printer. A USB printer can only work with one tab at a time. 1. Close any other browser window or tab with the POS open on that computer. 2. Close any other program that prints to this printer. 3. Print again. There is nothing to reconnect. Staff often leave a second POS tab open by habit. Keeping one POS tab per counter prevents this message. --- ## "The USB printer is unavailable" The POS cannot find the saved printer. It is switched off or unplugged, or this browser has lost permission to use it. The permission is lost after browsing history is cleared, in a new browser profile, in a private (incognito) window, or on a different computer. 1. Check the printer is switched on and the USB cable is firmly in at both ends. If the message clears, you are done. 2. If it stays, open ⚙️ **Settings**, then go to the **Printer** section. 3. Click **Settings** on that printer's row. The **Printer Pairing** window opens. 4. At the bottom of the window, click **Forgot** next to **Saved printer**. 5. On the **USB** tab, click **Add device**. 6. In the small window your browser shows, pick your printer and click **Connect**. 7. Wait for the green **Connected** label next to the printer. --- ## "The POS could not find a usable USB printer configuration" The device you picked is not a printer the POS can print to. It may be another USB device, such as a scanner or card reader, or a printer model the POS does not support. 1. Open ⚙️ **Settings**, then go to the **Printer** section. 2. Click **Connect** or **Settings** on that printer's row. 3. On the **USB** tab, click **Add device** and pick the printer again. Printers usually show their model name, such as **GP-58** or **Gprinter USB Printer**. 4. If the same message comes back, send us the exact model from the sticker under the printer. --- ## "The USB printer connection failed" Something interrupted the connection and the POS could not tell exactly what. 1. Check the power and the USB cable. Try another USB port on the computer. 2. Close any other program that prints. 3. Print again. If the message keeps coming back, send us a photo of the screen. --- ## "Web USB is not supported" or "Web Bluetooth is not supported" Web USB and Web Bluetooth are the browser features that let a web page talk to a printer. This browser does not have them. Safari, Firefox and every browser on an iPad are in this group. 1. On a Windows PC, a Mac or an Android tablet, switch to Google Chrome or Microsoft Edge and open the POS again. 2. On an iPad, there is no fix. An iPad cannot print receipts or labels, so move printing to a Windows PC, a Mac or an Android tablet of 10 inches or larger. --- ## "Cannot find printer IO" This is a Bluetooth message. "IO" means input and output, the channel the POS sends a print through. The device you picked connected, but it has no channel the POS can print to. Either it is not a printer, or it is an older Bluetooth printer. Only printers that support Bluetooth Low Energy, the newer power-saving kind of Bluetooth, can pair with the POS. 1. Check the printer's box or specification sheet for "Bluetooth Low Energy" or "BLE". 2. If it is not listed, connect that printer with a USB cable instead. --- ## The Device List Closes Straight Away on an Android Tablet You click **Connect printer** and the browser's device list closes at once or shows no printers. Chrome on the tablet does not have permission to look for nearby devices. 1. Open the tablet's **Settings**, then **Apps**, then **Chrome**, then **Permissions**. 2. Turn on **Nearby devices**. On older tablets it is called **Location**. 3. Go back to the POS and click **Connect printer** again. --- ## Any Other Bluetooth Message Other Bluetooth problems show the browser's own wording, often mentioning "GATT" or "adapter". 1. Check that Bluetooth is turned on for the computer or tablet. 2. Switch the printer off and on, and keep it within a few metres of the device. 3. Connect it again from the **Bluetooth** tab of the **Printer Pairing** window. 4. If it keeps failing, use USB for that counter. --- ## The Printer Pairing Window Opens When You Print No message appears. The **Printer Pairing** window opens instead, because there is no printer ready for that slot on this device. With Bluetooth this happens every time the POS page is closed or reloaded, because the browser drops the Bluetooth connection. 1. For a USB printer, on the **USB** tab, click **Add device**, pick the printer, then click **Connect**. 2. For a Bluetooth printer, on the **Bluetooth** tab, click **Connect printer**, pick the printer, then click **Pair**. 3. Close the window and print again. The POS does not resend the print by itself. --- ## FAQs **Will a failed print lose the order or charge the customer twice?** > No. The order and payment are saved before anything prints. Once the printer works, reprint from the order. **The printer shows Connected. Does that mean it will print?** > It means the POS reached the printer and tested the connection. If nothing comes out and no message appears, the problem is inside the printer, such as paper, labels or ribbon. See [Receipt Printer Will Not Print](/docs/receipt-printer-will-not-print) or [Label Printer Will Not Print](/docs/label-printer-will-not-print). **Why does my Bluetooth printer ask to connect again every morning?** > Browsers drop Bluetooth connections when the POS page closes, so it has to be connected again each time the page opens. For a counter that stays open all day, USB is the steadier choice. **My receipt printer works but labels still fail. Why?** > The receipt printer and label printer are separate connections. Each one is connected, and on Windows given its driver, on its own. Fixing one does not fix the other. **Why did the cash drawer stop opening at the same time?** > The cash drawer is cabled to the receipt printer, so the POS opens it through that printer. Clear the receipt printer message and the drawer works again. **One counter is fine and the other is not. Is my account broken?** > No. Drivers and printer connections are saved on each computer and browser, not on your account. Repeat the setup on the counter that fails. **I used a private or guest window and the printer is gone. Why?** > Private and guest windows start with no printer permission and throw it away when they close. Use the normal browser window you always use at that counter. --- ## What's Next Your printer is printing again. If nothing comes out and the POS shows no message at all, work through [Label Printer Will Not Print](/docs/label-printer-will-not-print) or [Receipt Printer Will Not Print](/docs/receipt-printer-will-not-print).