Scanner Probs

Hi
I have just added a Scanner on my son?s Pc. It is an hp Scanjet 3400c and the software installation went OK according to WinXP, it is there, I can see it, with Start -> programs or add/remove programs. The problem is when I try to scan a picture the message says, ?Scanner could not be initialized? (Scanner not found).
The above software came with the scanner?s CD for XP.
Then I downloaded from www. hp.com the latest software for this Scanner and for WinXPhome (sj652en.exe, 30.6mb), which I installed (I uninstalled the previous), but I still got the same message.
I use a USB connection, I tried parallel as well, and I have checked the cable for bad connection.
When I first added the Scanner the message said ?Scanner not supported?.
Any help/suggestions please?
Thanks
Yiotie