First identify which MKPOS application you are using and how the printer connects. A printer brand alone does not determine compatibility. Canon and Epson make different kinds of devices; direct thermal printing needs a compatible ESC/POS printer, not simply any device with Wi-Fi or Bluetooth.
Choose your printing method
| Application | Normal printer / PDF | Direct thermal |
|---|---|---|
| Web browser | Browser print dialog and a system-installed destination. | No built-in direct raw TCP or Bluetooth connection in the current web printing path. A thermal printer can use its system driver through the browser dialog. |
| Windows app | Compatible installed Windows driver, or a PDF destination. | ESC/POS TCP or paired Bluetooth Classic using an outgoing COM port. |
| Android APK | Android print dialog, compatible print service or Save as PDF. | ESC/POS TCP or paired Bluetooth Classic SPP. BLE-only and direct USB are not supported. |
Windows: installed printer
- Install the printer in Windows with its compatible driver. Confirm it can print from Windows before configuring MKPOS.
- Open Settings → Printer. Choose Installed printer — Canon / Epson / thermal / PDF.
- Select Refresh Printers and choose Printer Name. Leaving the name blank uses the Windows default printer.
- Choose Receipt Paper: A4 or A5 for office paper, or the width matching the loaded receipt roll. Match the driver's paper settings too.
- Set Copies, Color and Orientation as needed. Leave the Windows dialog enabled during initial testing so you can inspect the destination and paper.
- Save printer settings on this device, then run a Test Print. For a PDF destination, select the save location; a saved PDF is not physical output. Copies and the Windows print-dialog option do not apply to the special PDF path.
Windows or Android: network thermal printer
- Confirm the printer supports ESC/POS raster receipts and is connected to the same reachable network as the device.
- Obtain its IP address from the printer/network setup or the person managing the network. Do not use the web server address unless that machine actually runs your printer emulator.
- Choose Network thermal printer / emulator. Enter Printer host / IP address and TCP port. Use 9100 only if that is the port the printer or emulator listens on.
- Choose a thermal paper width, one receipt copy for testing, and enable automatic cutting only if the printer has a cutter.
- Save, check the connection, then print a sample receipt. Inspect the first and last lines, totals, Myanmar text and cut behaviour.
For CrossEscPos on the same Windows computer, 127.0.0.1:9100 is appropriate only when the emulator's TCP listener is running there. On a phone, 127.0.0.1 refers to the phone, not the PC: enter the PC's LAN address instead. Use a trusted network; raw printer traffic is not a secure public-internet service.
Bluetooth thermal printers
Windows: pair the printer in Windows first. In MKPOS choose Bluetooth thermal printer, use Open Bluetooth pairing if needed, refresh COM ports, and select the printer's outgoing COM port. A random COM port or an incoming port is not equivalent. Save and test. This path requires Bluetooth Classic, not a BLE-only printer.
Android: pair the printer in Android Settings, open the APK's Printer settings, choose Bluetooth thermal, allow Nearby devices when requested, refresh the paired devices and select the intended printer. A paired device being listed does not prove it supports printing. Use a Classic SPP ESC/POS model and confirm a real receipt. If permission was denied, review the app's permissions in Android Settings.
Web browser printing
Use Test Print or Print Receipt, allow the MKPOS print window if the browser blocks it, and select the printer or Save as PDF in the browser/system dialog. Review paper size, scale, margins and orientation there. Typing an IP address or COM port does not create a direct connection.
The current browser printer-name field is not proof of a detected local printer. The normal web page cannot use the Windows app's native printing bridge. If you require configured direct TCP or Bluetooth receipts, use the supported native application.
Paper, copies and document layout
Choose the roll's actual width, not the width you want the receipt to be. Direct thermal output uses common print-head defaults; unusual models still need testing. A4 statements and barcode documents use system printing rather than the direct thermal receipt route. On Windows, the A4 document printer can be configured separately; a blank selection uses the Windows default.
Receipt content and margins belong in Receipt settings. Printer destinations belong in Printer settings. Native profiles are device-specific, so test each checkout computer and phone independently. Keep unfamiliar technical settings at their defaults.
Connection success but nothing prints
- Check power, loaded paper, cover, paper direction and whether the device is paused or showing an error.
- Confirm the saved destination and paper match the intended printer. A successful check only establishes a connection; it does not verify paper output or protocol compatibility.
- Run one test receipt. If it fails, read the full error and note whether the problem occurred before sending or after partial output.
- For TCP, confirm the listener and address. For Bluetooth, confirm pairing, permission and the correct device/port. For system printing, inspect the print queue or print service.
- Before retrying, inspect the output and queue for a partially or fully printed job. Do not generate repeated copies or new sales.