HP window in XP

I am using XP and have installed drivers for HP scanner. I have installed drivers and scanner works. At startup I have a window that appears that says "This program updates your scanning software .You may see a message digital signature not found. Click yes to install. "
How do I get rid of this window?

 

You may have a lovely little programme called Backweb (or similar) installed via the HP software that came with your scanner?
This programme is pretty much spyware and downright annoying!
Check your start menu and/or Add/Remove programmes and uninstall it.
I'd suggest this may be a good time to install ad-aware and spybot - search and destroy. Do a search for download sites. Install and immediately update both for the latest definitions, and importantly click on their respective update buttons weekly.
You may be suprised at how much crud they find!