Trouble with Itunes on external drive.

I'm doing some work for my brother in law with itunes. He has a laptop with a small hard drive so he bought an external hard drive to store all his music. I setup itunes on the external drive and imported about 3800 songs, when i shut the laptop off for a day or two i turned it back on and started itunes and it was empty! Almost all of the folders were still in the Itunes music folder but the library was completely empty. I changed the default file location to store the songs and folders to the external HDD, rather than the default local disc in the My Music folder. Are there any steps i'm missing here? Thanks in advance for any help.

iTunes has an annoying habit of trying to demand using the My Music folder under My Documents. See if the files are there, then move them back to where you want them then reimport. I also think that if iTunes itself is not installed on the external drive then if you boot the computer without the drive attached, then iTunes may default it self back to My Documents/My Music if launched or if the systray icon is used.

Yeah, i noticed it creates a folder in My Music, that's why i changed the directory to the external drive. The strange thing about it was all the folders were still in the Itunes Music folder on the external drive except for one. I had to use a recovery program to get the folder back. I got everything organized again so i'll keep my eye on it for a while.