But iTunes libraries on external drives seem to be trouble at times. One can only hope folk will have a backup copy as noted at http://support.apple.com/kb/HT1751
So with that backup copy one should be able to restore as soon as the content copies back in.
For those that don't backup, I worry as they often explode on those that mention we do need backup COPIES (plural.)
Time Machine is pretty good but I've found if I want to be sure, I have no less than 2 backup copies.
Bob
Three Car Pile-Up: I-Tunes, Time Machine, External Hard Drive(s)
Help! The "Geniuses" ain't what they used to be and apparently I've lost a step myself, because this new version of an old problem has me tearing my eyes out. Too many new moving parts, I guess? Somebody here's hip enough to square this in minutes, I bet.
That's right: I've lost my I-Tunes library, and no kind of restoration I know brings all 230+ gigs back home. Rather, about 108gigs - that exact number, every time - reappear featuring duplicates all over the place.
HERE'S THE STORY.
1) This Spring my MacBook Pro was close to full-up. It had happened before with my last MacBook Pro, and I found that scoring a Lacie MiniHub external HD did the trick. This time I got a larger, 1TB Lacie, moved my I-Tunes library to that sleek black box and enjoyed a life of rigorous ripping and downloading.
2) I bumped into the Lacie MiniHub I had used on my previous Macbook Pro and realized there were audio files in its old abandoned ITunes library I hadn't heard in years. They were added and copied and all was grand. I even learned, this time, how to bring playlists with me when I switched Itunes library locations, something that's very important to me (because I'm a sentimental fool.) Up to this point I had reunited past folders from past libraries, consolidated and reaped the benefits. The Time Machine seemed to have nothing to do with it.
3) Then I left town, with my Macbook but without the hard drive that housed I-Tunes or the Time Machine/Time Capsule that performed constant backups AND, it turned out, had been backing up my Macbook to the Lacie hd that housed all the music. I avoided opening ITunes throughout the trip, not wanting to know what might happen if the program went looking for a pointer to a library that wasn't there. I thought I was being careful, and listened to my IPod (without syncing it) until a long trip ended, I returned home and reattached my laptop to the hard drive.
4) Something was wrong. I was immediately asked to "create" a new I-tunes library, but whenever I tried to re-establish the library located on the external drive that had worked so well, the contents of I-tunes added up to merely 100gigs and NO PLAYLISTS. I fiddled around with the "backups" included on the drive, because Time Machine had been backing up the entire MacBook to the external hd. Nothing worked, I panicked, and now there are a half-dozen "Itunes Media Library," "Itunes Library" and "Itunes" folders on the external drive, each of which leads to the same silly 108gigs.
5) I thought it was time to talk to the Geniuses, at this point. They were helpful, in the sense that I was sold another $110 external hd that was tiny and wouldn't be necessary to unplug, I guess. Because my Lacie hd still claims to have the 230 gigs it should somewhere inside of it, I was instructed to copy the entirety of the LaCie to this brand new drive. That way it would be (inaccessible but) safe. Then I was to scroll, with and without the help of the Time Machine, through every "Itunes Library.xml" available (especially those predating when I left town), until I could "add to library" and come up with the 230 gigs, at which point I should save that complete and restored-ish library to the new hd as well. My Playlists, the Geniuses advised, were _probably_ lost forever. When I seemed exasperated, I was cautioned. The great Genius said that in life, we all must maintain things: our gardens, our homes, our health and our libraries. I'm not sure where and how I failed here, and I wish the condescending Genius would have at least supplied that info before his philosophical speech.
6) I am rather useless on the Time Machine. Today I tried flipping back to the backup of I-tunes from before I left town, but I couldn't seem to get at the relevant files. Is this even the right path, or should I start with the question of the 127gigs missing on my Lacie hard drive... do I need to break out that original Lacie hd I copied to the new one months ago? And where do I find those playlists, anyway? I know I once read of a certain file meant to be copied to one place and erased in another that would restore playlists.
I want to apologize for my lengthiness and beg for some insight. Clearly Apple Stores are meant for servicing phones at this point and they have nothing to tell me. Has somebody been down this road - or part of it - before? Are there details I could provide that would help you help myself? Thanks for reading and I look forward to hearing from y'all. Sorry if you've heard this all before but certain variables make this a novel problem for me. Thanks in advance for solving all my problems and inciting a worry-free future.

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