Detailed instructions for the firmware.
Step: 1: Report on the current firmware version
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To find out the version you can print the report: Press 3 times Menu, "System Setup" will be displayed, click OK. Use the buttons to the left and to the right, to find the word "Reports", and again OK. Using the button left-right, find the word "Configuration" and press OK, confirm the print. You will receive 2 sheets - "Configuration Report", it will be the version of your firmware.
There is one more possibility to find out the version of the current firmware.
You need to press:
Menu - # - 1 - 9 - 3 - #
After that, you will see the current version on the screen.

Step: 2: Firmware version in the report
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After the printer prints the report, find in it:
OS Version (current firmware version)
Possible firmware versions are 2.50.00.85 or 2.50.00.87
If the letter F is present in the firmware version of the printer, then it is already stitched. Therefore, you do not need to flash it.

Step: 3: Preparatory stage
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Use the USB cable to connect the machine to the computer. Wait for it to be determined. To avoid conflicts, disconnect all USB devices that are not required for this procedure.

Step: 4: Firmware
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Note: If you have Win7 or Win8 on your computer, you need to check the "Run this program as Administrator" option in the properties of the usbprns2.exe file.
To flush the printer, drag FIX_NU_MA_wc3220_v2.50.00.99.hd to usbprns2.exe
The console window will appear on the monitor, after it disappears the printer will reboot.

The firmware was successful!

Step: 5: The final step
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Pull or glue the chip, check for paper.
P.S. there is no chip on the start cartridge.