FirewallQ please use the edit button, it makes life so much simpler when formulating replies to long responses such as yours
Windows Update (using its completely manual mode -- the lowest on the list of its four options) failed and showed error code 8024400A but my computer's network connections showed it had downloaded about 3 million bytes before the error code popped up
If you receive Windows Update error 8024400a, 8024400d, or 8024400e while checking for updates, it might be caused by a connection interruption between your computer and the Windows Update servers. Close Windows Update, wait 10 to 15 minutes, and then run Windows Update again. You can also wait for Windows Automatic Update to run at its next scheduled time.
Source:
Windows Update error 8024400a, 8024400d, or 8024400e
By the way, 3,000,000 bytes is about 2.96MB, which if you had a connection error to the server, would probably be about 1 update, hence why you got the "configuring updates" message very briefly, it was sorting out the 1-2 updates it HAD managed to grab. As for the 1,000 or so you saw afterwards, I would expect to see that, because WIndows update would be trying to reconnect to the server.
Is this "configuring" message normal under these circumstances?
If you have been connected to the update server, even for a brief period of time, then yes, perfectly normal. See my above post, cba to repeat myself.
I don't know whether the firewall had always said "CONNECTED" from the very first time I set up my computer and before I connected to the internet --because I had not checked it at that point -- did you?
No, admittedly I didn't. As I said though, my machine had been "live" (that is had Windows installed, for less than 30 minutes at the time of my check. The chances of me being infected, especially considering that my security was ALREADY on and updated (grabbed the update files before I installed) are next to none. Therefore, normal behavior. (and yes, when I checked the firewall settings I was disconnected from the internet)
After I did system restore to the time of first setup of the computer, Norton's firewall and internet intrusion functions would not allow me to turn them on; every time right after clicking them on, they would always go back to the "off" position.
Possibly a virus, possibly Norton being screwy, personally I'd lean towards the latter, but as kegobeer said, does no harm to check.
I have not done any file sharing or gone to any webpages except for a public Wifi welcome and accept page (in order to access the internet to use Windows Update).
For someone so paranoid about security... taking an unprotected machine onto a public hotspot is not exactly a brilliant idea.
Im still willing to bet its Loopback, but I won't completely discount the notion you may have picked something up. All of your symptoms can be explained by other stuff though, just saying.