I don't know for sure why the bar-codes don't print on my M475dn, or (only sporadically) on your M401, but note:
- There is absolutely nothing which would select a bar-code font from an add-on bar-code DIMM or cartridge, etc.
- Two soft-fonts (with font names BC390C and POSTNET) are downloaded within the print stream.
- These soft fonts are in the original Format 0 (bitmap) format, use of which has been deprecated since the LaserJet 4 (about 1992?).
- This font format is perhaps no longer supported on modern devices?
- The PCL also includes a number of obsolete and/or invalid sequences, or just somewhat confusing combinations, which may (or may not) contribute to the symtoms you are experiencing: e.g.:
Offset Type Sequence Description
------------- --------------------- ---------------- ----------------------------------------------------
. . .
. . .
. . .
0000031589 PCL Parameterised <Esc>(1X Primary Font: Select by ID (identifier = 1)
0000031593 PCL Parameterised <Esc>(1@ Primary Font: Select Default (1 = unknown/illegal value)
0000031597 PCL Control Code 0x0f <SI>: Shift In - select Primary font
. . .
. . .
. . .
0000037122 PCL Parameterised <Esc>(2X Primary Font: Select by ID (identifier = 2)
Comment The following sequence is considered to be obsolete:
0000037126 PCL Parameterised <Esc>(2@ Primary Font: Select Current Character Set
0000037130 PCL Control Code 0x0f <SI>: Shift In - select Primary font
So I think that you need to talk (some more) to your software supplier, about:
- Updating their output for more modern devices;
- Why use of add-on bar-code font DIMMs/cartridges has been suggested, when the generated print job makes no attempt to make use of them.