Purchased music won't sync (4.9)

[Fantomonkey]

Since my update to Windows Itunes 4.9 my purchased music won't sync onto my ipod. Ive searched and see similar posts, but here is whats happening on mine that has me confused.
The purchased music folder in Itunes on my pc shows all my purchased music.
That music shows up just fine in the library and has the check mark next to it like everything else. (So on the iTunes side everything seems fine)
On my iPod itself, in the playlist section, there is no list for purchased music (there previously was). Also some of this music was in the On the Go playlist as well as the top 25 playlist, but it no longer shows up there. Also when I browse by Artist, song, or album title I cannot find any of the music purchased from the iTunes store.
So basically everything looks fine on the PC side but isn't moving it to the iPod (even though it was on there just fine before. I did a check under the Advanced tab and clicked "Check for purchased music" and everything was up to date and I can play it fine on my PC.
This is the only machine that I've had iTunes on and the only machine I have used my iPod with.

Details about my hardware:
Windows XP sp2
iTunes v 4.9
40 gb iPod 4th gen

[honeybee1236]

Did you update the iPod fimware? If purchased music doesn't transfer then make sure the iPod is up-to-date using the updater.

[Fantomonkey]

I just double checked that and I have the latest firmware on it from the iPod updater.

[honeybee1236]

Make sure that the iTMS songs are authorized and try resetting the iPod also.

See this Apple document:
http://docs.info.apple.com/article.html?artnum=93867

[Fantomonkey]

I read through that link and double-clicking and authorizing the pc did the trick.
I got a message saying this is the 2nd (out of a possible 5) PC authorized for the music. Strange thing is this is the PC I downloaded the music from & my iPod has never been hooked up to any other machine. Either way it works now.
Thanks a bunch for the help