Code 400: unable to read file - doesn't appear to be gcode (with untouched gcode that I ran successfully last week)

EDIT: I tried loading my job from a USB drive for the first time and it worked, so it’s sort-of fixed.

Today I’ve run into a new issue and am unable to run my machine. I created a new gcode file, something very simple to surface a spoilboard before running an actual job, and I got the error:

{“code”:400,“message”:“Unable to read file - doesn’t appear to be GCode.”}

I rebooted and got the same problem. I compared my new gcode with some old gcode and nothing really stood out that would make it not work. Then I loaded some gcode that I was able to run successfully over the last couple weeks and I got the same error… How is this possible? None of my gcode is working and I can’t run a single job on my machine. This, in addition to the networking issues I’ve had on this machine, are starting to make me regret my purchase.

I’m running version 1.2.1 and I have a stable internet connection between my laptop and the Onefinity controller.

I’ve seen other posts where people have run into the same error code but as far as I’ve seen that was a different root cause.

Here is the file that I tried running today: (58.2 KB)

Here is a file I was able to successfully run recently: (11.2 KB)

Just an guess:

You are including N-Codes (basically line numbers). I don’t know if the Onefinity system understands them or not. My CAD/CAM software doesn’t produce them.

This may help: N-code instead of G code - #2 by wolfkabal

Hey Atroz, hey all,

line numbers do no harm (test it: line_numbers.ngc), but already the G-code Standard stated that omitting them is normal practice. In LinuxCNC G-code documentation (after which the controller g-code was patterned) their use is discouraged:

24. G Code Best Practices


Don’t use line numbers

Line numbers offer no benefits. When line numbers are reported in error messages, the numbers refer to the line number in the file, not the N-word value.

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I’ll look into this, but even if line numbers were contributing to the problem that doesn’t explain why my old unchanged gcode is no longer working. I’m categorizing this as a networking issue for now since it works fine when I load it from a USB drive.

Hey Alexander,

these files load on my controller with no error.

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Try renaming your file to the USB without underscores and dashes. Depending on your firmware version, those characters can be problematic to reading the file. Search the forum for this issue and it’s limitations.

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