When I connect a DeskJet 810C to my Win XP Pro computer using a USB cable I get "USB Device not recognised".
The USB ports are OK because I can connect either a Mouse or FlashDisk to each.
The USB cable and Printer are OK because I can connect to another machine OK.
What's the first step to Troubleshoot this?

Mark

Have you installed the drivers for the printer yet? Many USB printers require you to install the drivers first. Some will tell you to connect the USB cable at a specific point during the install. Others may require you to connect it, then install drivers. Check the manual and follow the install instructions for the printer, many printers don't like it if you don't set them up EXACTLY according to instructions.

Just to make sure, I run the unistall from the HP810C CD and rebooted.
I then plugged in the printer, with the CD inserted (as per the instructions.

It seems that it is not even getting as far as loading the drivers because I immediately get the "USB Device not recognised" message.

XP pro has the drivers for the HP 810C in its driver database. I have one hooked to a XP machine and it recognizes and loads the drivers.. your problem is either with the printer of with your USB.

do you have the usb 2.0 drivers for your mobo installed? and have you hooked up the printer directly or thru a USB hub?

The computer supplier told me USB 2.0 had been enabled - how do I tell?

When I expand the USB Controllers node of Device manager I get
Intel 8280 1EB USB Universal Host controller - 24D2
another for - 24D4
another for - 24D7
another for - 24DE
Standard Enhanced PCI to USB Host controller
Unknown Device
and then 5 entries saying USB Root Hub

Does this help?

Did you receive a disk with the computer that contained the drivers for the mobo? if you did the usb 2.0 drivers should be on that disk. if it is an intel disk they have a update feature included on your disk and it will tell you if USB 2.0 is installed.

in fact I would say that USB 2.0 is NOT installed since if it were you would have an entry that says.
"USB 2.0 Root Hub" under the Universal serial bus controllers category in device manager.

BTW does your install of XP have service pack 1? the USB 2.0 support in XP is in SP1.

Yes my install is SP1 of XP Pro.
I have done what instructed to enable USB 2.0
BUT
SiSoft Sandra still reports USB1.10
I don't know if this is correct, but can find no native Windows way of reporting the USB version

yuor board has usb 1.1 AND 2.0 ports. from what you showed of what device manager says the USB 2.0 root hub is not functioning.

you list your board as an 865 is it an intel board or asus etc. whichever it is you should go to the manufacturers site and download the USB 2.0 drivers.

you can also take a look on this site

http://www.usbman.com/winxpusbguide.htm

The board is Intel.
The link that you provided seems to have conflicting information saying, on the one hand "the latest USB2.0 driver for XP is available at ..." but then "the only way to get the latest USB driver is to download SP1" When I asked the MS Update site to scan for updates needed, it didn't come up with a USB driver.
My about box confirms that I have SP1 loaded.
The instructions from Intel to enable USB 2.0 was to go to the properties page of each USB device and go "Update Driver"
I have done all that. (Would I need to have the XP CD in for this to work?)
It may be true that I don't have USB 2.0 working - but is that the critical issue? Remember that a mouse or a FlashDisk both work in the same port. The printer is 1999 and so should be quite happy with USB 1.10.
Or have I missed something here?

could just be the printer. I have installed my 810C HP on two different XP machines and in both cases it was recognized and the drivers were automatically installed.

have you tried unistalling the "unknown deivice" in device manager and rebooting and see it windows recognizes it?

http://h20015.www2.hp.com/en/docume...hpdeskjet810483&docName=bpd06656&cat=prodinfo

That printer does not require USB 2.0, so most of the above doesn't really matter as long as your USB ports are working correctly which you have already said they do.

I never said that the printer required USB 2.0. but I have seen some usb devices(usb1.1) not work properly when the USB 2.0 drivers were not installed.

http://h20015.www2.hp.com/en/docume...XGR3UOSQ?reg=na&cc=us&docName=bpd09005&lc=en&

This should help you.