"brother_ql -b pyusb discover" doesn't find the printer

[the-powl]

When typing
brother_ql -b pyusb discover
into the command line, I only get the
deprecation warning: brother_ql.devicedependent is deprecated and will be removed in a future release
message but nothing else, although I have a working QL-800 attached via USB. I can print on it via the P-Touch software anytime.

Windows 11
brother-ql 0.9.4
pyusb 1.2.1 (also tried 1.0.2, doesn't work)

Any ideas what goes wrong? Without the discovery I can't obtain the printer_identifier.

[FriedrichFroebel]

Is the "Editor Lite" mode disabled through the corresponding button as per the docs?

[the-powl]

yes, the "Editor Lite" mode is off

[madeinaus]

Install libusb, AND use the libusb wizard to install libusb as a 'filter' into the printer USB driver chain. pyusb is cross-platform, and can't see any USB things at all on windows: all it can see is libusb. libusb is a platform layer, not a printer driver, and on windows, needs to be inserted into the printer-driver chain so that it can see what happens.

When you have inserted the filter, libusb can see the thing the filter is attached to, and pyusb can see the things the libusb can see.