Problem you may have in iTunes 7

Question

If the ituneslibrary data file is missing from your my music folder..go to the previous library folder and copy ALL the files there and put it into the itunes folder, then delete the previous libraries folder...that should help...it did that to me once before, so good luck

Answer 1

You can sync multiple iPods with one library:
How to use multiple iPods with one computer.
iTunes doesn't know about multiple libraries. You have to tell iTunes which library to use.
If the library was created by iTunes, holding the Option-key on launching iTunes, will enable a menu to choose one.
If you want to switch to another library, quit iTunes and launch again while holding the Option-key
If you created multiple libraries with one of the 3rd party applications I mentioned in my previous post, you have to quit iTunes too, run the app. and launch iTunes again.
The difference is that these apps. not only save the 'iTunes Library' file, but also the preferences file.
iTunes can only manage one library at a time. That's why you have to quit and relaunch.
You can manually manage your iPod with multiple libraries.
It's about the same as described in this article:
Using iPod with multiple computers
M
17' iMac 800 MHz, 768 MB RAM, 200 GB HD, DL burner   Mac OS X (10.4.8)   iTunes 7.0.1