Hello. My HP DeskJet 845c printer doesn't work on Debian testing (etch) with 2.6.17.4 kernel. I have installed cupsys, hpijs. With lsusb I can see my printer:
SlipKnoT:~# lsusb
Bus 001 Device 001: ID 0000:0000
Bus 002 Device 001: ID 0000:0000
Bus 003 Device 005: ID 03f0:0904 Hewlett-Packard DeskJet 845c
Bus 003 Device 004: ID 1267:0201 Logic3 / SpectraVideo plc A4Tech SWOP-3 Mouse
Bus 003 Device 001: ID 0000:0000

But lpinfo says, that no printer found:
SlipKnoT:~# lpinfo -v
network socket
network beh
direct hp:/no_device_found
network http
network ipp
network lpd
direct parallel:/dev/lp0

In localhost:631/admin?op=add-printer Device: I see only hp no_device_found.. Some packets are missing, needed programs aren't running, modules are missing in kernel?
Sorry for my bad english, please help

If you are using hplip to drive your printer.
Try as superuser

hplip restart

and then

cups restart.

In Debian, I don't know the precise commands to use. Maybe do a google search, unless you know them already.

Thanks for reply, but restart doesn't help (by the way it's /etc/init.d/hplib restart ). Any ideas? That printer is killing me

I have access to the same model printer - it's driver appears to be a 895c.
#lsusb
Bus 004 Device 003: ID 03f0:0004 Hewlett-Packard DeskJet 895c

When I plug it in and turn it on I get this.

#dmesg grep | tail

usb 4-2: new full speed USB device using uhci_hcd and address 3
usb 4-2: configuration #1 chosen from 1 choice
drivers/usb/class/usblp.c: Disabling reads from problem bidirectional printer on usblp0
drivers/usb/class/usblp.c: usblp0: USB Unidirectional printer dev 3 if 0 alt 1 proto 2 vid 0x03F0 pid 0x0004

With the printer connected and switched on what does dmesg show after bootup? Did your printer show up.

Did your kernel come with the distro or did you compile it yourself? In any case,
if you have access to the source in /usr/src/linux-whatever your kernel is,
try this (you may need to be superuser to do this).

In a terminal do;
#cd /usr/src/linux-whatever...
#make menuconfig (text based editor)

(#make xconfig works in KDE. #make gconfig for Gnome).

Device Drivers - USB - USB Printing (must be selected)
USB Mass storage should also be selected, this enables scsi functions which some printers require. When I scroll through dmesg after booting up, I see my HP2450 printer registered as an scsi device. Not sure about the 845c, but it wont hurt to select these options as they are needed for other devices.

Also, Drivers - SCSI Device support - device support - disk support - generic support - probe all LUNS.

Restart hplip and cups.
If this is all correct then you should have printing.

(As you are using a testing version, there may be a
problem with that. In which case a bug report is appropriate).

If not you then you could install a different kernel or recompile the one you have. (Seperate subject altogether).
If you have a spare partition or hard drive on which to intall a stable version of your favourite distro, you may be able to determine whether it is the distro or the printer at fault. Or, another computer with linux installed.
Hope this is helpful.