Careful! Moving the media folder to an external drive MAY cause missing tracks.
I moved my iTunes media folder form a macbook pro 13" to an external Seagate drive, using the method prescribed in the Support site. [http://support.apple.com/kb/ht1449] The result was odd: many many tracks in the iTunes library now had the ! next to them, and the files were not on the drive. It was random: an album might be missing tracks 1, 6, and 8 with the others intact. I was able to recover the files from a backup. I passed it off as a one-off glitch. Recently I bought a 15" retina with a larger drive, so I moved the media folder back to the computer. Again I used the Apple method. Again the result was many random missing files, i.e. about 5GB of a 50GB library.
On spec, I deleted the contents of the iTunes media folder on the computer, and copied and pasted the contents of the iTunes media folder from the external drive. In iTunes, if I click on a track with the ! next to it, the player quickly finds it. To be clear, they never went missing from the iTunes library, but the files themselves went missing. So at least in my case the Apple method of moving the media folder was resulting in files going missing.
My issue seems identical to yours!
Only thing is, I woke up my laptop this afternoon, finding that iTunes was, for some reason, reconfiguring itself. Couldn't understand why. Then the window opens, and music that had been there only a few hours previously had vanished.
They're still in the folder in My Computer, but I can't drag the files over, opt to open in iTunes, or go through the Add Files To Library option. It'll let me open in Windows Media Player, but screw that for a joke.
(And yes, I am aware Windows isn't the best for running Apple stuff, but I have never had a problem before now).
I just had the strangest thing happen in iTunes. I was just listening to music on my iMac and I selected a song that I hadn't listened to for a while. iTunes could not find the song and asked if I wanted to locate it so I clicked on locate assuming something had just happened to the link. To my surprise when I tried to find the song on my hard drive I discovered all the files from both albums of that artist that I owned were missing. I wasn't too worried about it because I had a back up so I copied the files for the 2 missing albums back into my library from my back up and restored the links in the iTunes library.
Just to be safe I decided to compare my iTunes Music folder with my back up Music folder. I got info on both folders. I was shock when I saw the size of my iTunes Music folder was only 48GB, because my library is supposed to be over 300GB. I started looking through all the folders in the iTunes Music folder, which was organized by artist, and found most of the artist folders were empty. Some of the artist folders still had ablum folders in them but all that remainded in those folders were jpegs of cover art. All the music files were gone. I have not idea how 85% of my music library could have been deleted.
iMac, OS X 10.9, iTunes 11.1.3
It's not strange at all. iTunes has a serious problem (or multiple problems) that they either cannot figure out or don't care about. I gave up and bought a non-Apple music player. I installed MediaMonkey and imported my entire iTunes library, then got rid of iTunes. I have had no problems since. I've paid Apple THOUSANDS of dollars in iTunes downloads, multiple iPods, iPhone, iPad, etc. Their inability to resolve this problem has caused them to lose a customer, at least for now with regard to their music business.
turing, I believe I have posted them in this very topic, which is why I am still getting email reminders of replies. I have resisted upgrading my iTunes lately because once I get something stable I have finally learned to avoid changes. In my case, the songs were deleted only during the sync process, and only if I had the "reduce bits to 128" setting turned on, and even then it would only happen the very first time I synced new songs that I had ripped. I even tried ripping the tracks and then marking them as "Read Only" which either (a) should have prevented iTunes from deleting them, or (b) at the very least I would have expected an error message. But no, the songs still got deleted on the first sync. After restoring them to my hard drive and removing them from my iPod and rerunning the sync process everything would work. So for a while my workflow would be:
1. Rip a disc
2. Update tracks / album / artwork as desired
3. Copy all of the .mp3 files to a "temp save" directory
4. Sync to my iPod to load the new music onto the device
5. Copy everything back from the "temp save" directory to restore those tracks that were deleted
6. Sync again
I thought there was a time / date issue because I discovered that my NAS device (from Netgear) was improperly modifying the clock for daylight savings time. I thought that since I was storing my music files on that device, and it was one hour in the "future", that the tracks were being deleted because iTunes refused to see them because their date/time stamp was off. I fixed my Netgear NAS device, and the problem persisted.
Next I thought I had fixed everything with an iTunes upgrade, but it turned out that the "128 bit" setting had been turned off during that process. I prefer to have that setting on so I can get more songs on my device; I didn't buy the 160GB model because I only wanted a few tunes, I wanted to have as many with me as I could. As soon as I turned the 128bit setting back on, the problems came back.
So now I just leave that setting off, and I put fewer songs on my iPod.
I am running an iPod Classic 160GB on Windows. I could open a "file explorer" window and show the contents of one of the album folders, and I could watch the files disappear as iTunes sync'd them. I was going to offer Apple techs the ability to view my desktop to show them that, but it turns out that they can't do that on a Windows system, plus as I mentioned above, they weren't going to help without me paying because my hardware is outside of the free service window, and they don't support iTunes separately
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Actually, my issue is that I have an iPhone 5s (running IOS 7.0.2 of course) and after I transfer some songs I dumped from a CD, I move them to my iTunes Library on my computer, then drag them to my iPhone. About 12 hours later, some songs are GONE. Completly disappeared from my iPhone's music app. My computer's iTunes is up to date too. Anyone help?
First piece of advice is to backup your library in a way which lets you be aware of any further issues. Are you using the option to sync lower bitrate songs to the device? This may be a factor in some instances of this behaviour.
The blue text in the previous post is a link to an iTunes backup strategy.
When your device is connected on the summary tab for it there is an option that reads something like Convert higher bitrate songs to <Choice of bitrate> AAC. It is used to let you store more songs in the limited memory of a device.
Itunes continues to wipe songs randomly from my ipad and iphone on a daily basis. I just accept it now that it is a broken product and use a 3rd party app to back up and reload whenever there's a particular need.
I know people are trying to help with the technical suggestions, but it really misses the point that a software with this many uses should just be click and play without needing technical support every verse end.
I am flabbergasted that Apple haven't yet sorted this problem out.
As of Mavericks, whenever I run iTunes, it hits my Synology NAS continuously, whenever iTunes is running. I wondered what it was doing until I started noticing songs disappearing from albums. Now looking at dozens (or perhaps more) of albums that are no longer complete.
I know this isn't constructive, but iTunes is the most foul, stinking pile of **** I have ever interacted with. It's the worst thing about Apple by a long shot.