Comment 11 for bug 1811504

Yes, I'm using a USB connection.
I tried also via wireless but it fails the same way (i/o error code 9) when it starts scanning.

I believe the relevant part of journalctl is:

io/hpmud/musb.c 1566: invalid HP-ESCL-SCAN channel=26
io/hpmud/musb.c 975: removed HP-ESCL-SCAN channel=26 clientCnt=0 channelCnt=0
http.c 263: unable to open HP-ESCL-SCAN channel
...
http.c 322: invalid http_status=409
http.c 328: dumping len=127
http.c 153: hpmud_read_channel failed retrying (2) more times)
http.c 153: hpmud_read_channel failed retrying (1) more times)
http.c 153: hpmud_read_channel failed retrying (0) more times)
http.c 157: read_stream error stat=49
http.c 189: -read_stream() bytes_read=0 s.index=0 s.cnt=0 stat=1
bb_escl.c 828: http_read_header returned error code(1) hence exiting..
(attached full log)

I'm wondering why there is a 409 http error code.. it looks like there is some conflict or broken communication somewhere, maybe because of unreachble HP-ESCL-SCAN channel.

The scanner works ok with vuescan proprietary engine so the issue seems related to sane/hpaio backend.