iPod Touch update

I Downloaded an update to my iPod touch and it downloaded for about an hour.

when the upload to the iPod tries to go i get a message:

"the iPod could not be updated . An unknown error occurred (4000)"

• this after my PC "extracted" the update with no error messages and tried to update the IPod

So I don't think my synching is working now...

I'm confused...I have exited both devices and tried again after 30 minutes but still a problem

A while ago when i had issues on an update I was able to do it directly onto the iPod but forgotttn how to do that now..

Any help will be appreciated as I want to add some more purchases but nervous they will not synch to the iPod.

Thanks - I'm not a very Apple-savvy person - the iPod touch is all I have (it is a pretty know device)

Thnaks

Papa-Roy