How do I transfer my library on my itunes with a flash drive?

I have my itunes library at my Mom's and I want to transfer it to my girlfriends pc with a flash drive. I uploaded about 20 songs to try it first. I can download them to the new pc and import them to her itunes program, but when I remove the flash drive, I get a message that the songs are not able to play because the pc can't find the source of the music file.

How do I transfer my library on my itunes with a flash drive?
You need to back up everything you have on itunes to a disk. Have you noticed after down loading itunes will ask if you want to back up what you have just down loaded.. Thats because if your computer goes down or you buy a new one all the songs you bought are on that disk. Now you can't play them on your cd or car cd player. But if you have itunes it will read the codes and restore what music you bought on your pc or mac.as long as you have your pass word.
Reply:You need to make a new file source create a folder in My Documents and send the files their from the flash drive.