As on your screenshot I couldn’t find any error detailes (maybe the licence activation window is hiding it or I am blind :)) I have no idea. BTW are you using a cool theme for your XP or is it vista? As this version of CAVS does NOT support windows vista. You may try to reinstall it if something goes bad. During the install its advisable to turn off all of your security software.
I think you can uncheck the box and just click OK, no activation is needed. Did you chose Cancel, and uninstall CAVS? What about the message in the box behind: “During configuration some utility returned error”?
This is a really odd one. The error message you’re getting isn’t in the list of internal CAVS error codes. It’s possible the error message is being generated by the installer which would undoubtedly have its own error table. I’d be inclined to go to http://support.comodo.com, register (if you haven’t already done so) and lodge a support ticket on this (including the screenshot you posted here).
Please note that your forum login is different to your support cebntre login in.
When support come back with a response, can you please report the results here for the benefit of others.