Hi,
You can certainly do this. Go to the iTunes preferences and you will find a section that indicates where your iTunes library is located. (There is a Browse Button there)
First though, RIGHT click and COPY your iTunes music folder from its current location, (My Documents/My Music, I think) over to the new drive. You are doing a copy, instead of a MOVE, in case anything goes wrong. Do NOT move the application, which should be in your program directory.
Now go to the preferences of iTunes and find that section of the preferences that indicate where you have your music. Click on the Browse button and make your way to the new external HD and the copy of the iTunes music folder that you have just moved there. Choose it and close off preferences. Close iTunes and relaunch. It should now be looking at your new location.
Hope this helps
P
I have a laptop (running Windows XP). Since there is limited memory, I purchased an external hard drive to store my music files. Unfortunately, it seems that the iTunes music file actually needs to reside in the C: drive (hard drive). Does anyone know how I can open iTunes and have it use the files from my external drive?
Thanks

Chowhound
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