Artist/Album, etc. ID tags missing

My guess is that the problem files will be in mp3 format and have multiple tags that are not fully synced with each other, and some internal change to iTunes is making iTunes read data from an incomplete version. You may need to use a third party tag editor to sync the data or better yet distil it into one tag that has all the information. For best results each file should have a single ID3v2.3 tag.

An alternative approach would be to use the right-click context menu in iTunes to Convert ID3 Tags... > None a few times to remove all existing tags and then Convert ID3 Tags... > v2.3 to build a fresh tag with the information still held in the iTunes database, you would then close, temporarily rename the iTunes Media folder, use the shift-start-iTunes method to open a recent version of your library in the Previous iTunes Libraries folder that has the data that you want to recover, use a script called ExportImport to export the necessary information, close iTunes. restore the original name of the iTunes Media folder, shift-start-iTunes to reconnect to the original library, then import the exported data.

tt2

In case it isn't clear this is a user to user support forum. Apple aren't going to read your rant. Use iTunes Feedback.

Perhaps I misunderstood your original post. I read it as saying that the data used be there in iTunes, but isn't any more. To the best of my knowledge iTunes doesn't have any features for independently correcting metadata, but there are occasions when it can reveal changes that have been made externally. As given iTunes works best with mp3 files that have a single ID3v2.3 tag. If you are importing files that have had tags written by other software there may be multiple tags which are not necessarily in sync with each other. Mp3tag is a good tool for tag cleaning. If the you're adding new files into iTunes that are set out in a standard <Artist>\<Album>\## <Name>.<Ext> layout then I have another script called TagFromFilename that can read in details from the path if the tags aren't completed correctly. You need to make sure that iTunes isn't going to copy or rename the files before you add them to the library by turning off the options to Keep... and Copy... if you want to make use of this method.

Each item in your iTunes library has a unique identifier. The aim of the process I outlined above is to access an older version of your database that has the correct information, rename the media folder so that iTunes cannot read the current versions of the metadata stored in the corrupt file, read the old versions of the fields that have been corrupted and write them out to a text file along with the unique ID of each track. After this you reconnect to the current library, restore the media folder name, and the script reads back the data applying it to each track in turn. Depending on the size of your library and the tweaks that need to be made to the script it is probably in the order of 15-20 minutes work to recover the lost data, as long as it exists in an older version of the library file in your Previous iTunes Libraries folder.

There is a section in the Action subroutine that begins like this:

' Comment out details you want to omit, remove the quote to include

WriteLine "<Location>" & .Location ' Not so useful if working with missing tracks

WriteLine "<Name>" & .Name

WriteLine "<SortName>" & SortValue(.Name,.SortName)

You can comment out any field that you don't need exporting by adding a leading single quote mark to the line.

If you want more details or a step by step guide, feel free to ask.

This is the original thread that led to the script if you are interested.

See also Backup your iTunes for Windows library with SyncToy.

tt2

You're welcome.

When iTunes imports files that don't have a valid tag (some mp3/aac files and all .wav files) its uses the filename as the track name complete with any leading track and disc number that might be there and sets album and artist to blank. It stores such items in the Unknown Artist/Unknown Album folder.

I wonder if it is possible that the tracks were never tagged, or had their tags cleaned at some point, and something prompted iTunes to reread them. 😕

tt2

Was there some incident where all of your media was imported into a new library, as opposed to the data that was in the (then) current library being corrupted? Select one track you can identify that is in the active and old version of your library. Export the information from one version, rename the exported file (I should really time stamp these) then export the other. Compare the IDs. If they are not the same then that probably explains what happened, a mix of metadata that wasn't correctly embedded followed by some crash which involved the library being rebuilt.

tt2

So it's not just the tags that are wrong but the audio too? Are either of Apple Music or iTunes Match involved? Is there a device that has any of the correct data?

tt2

1. The image is typical of the results of importing files that are untagged into iTunes. Often this will be files in .wav format but tags can be stripped from .mp3 or .acc files too. See Any software that can rebuild iTunes songs lost to Unknown Artist/ Unknown Album for a thread where I tacked a similar problem in the past. What I cannot see in that image is the file type, but I cannot think of any obvious mechanism for deleting that data, particularly from store purchases which, doesn't involve some kind of user error.
2. You haven't answered the question about iTunes Match. I know there are some people that like to discard say album and track number data, but they generally keep at least the Artist name as well as the track Name, so again all the obvious signs lead to missing tags, rather than randomly modified tags. On the other hand some kind of iTunes Match fail might explain how you have media that you didn't actively select. Again you would still have to make some effort to actively download the content since iTunes doesn't automatically download the iTunes Match library.
3. Again, this looks like untagged media, iTunes picks the filename and uses it for the Name. Any other information that might be there in the filepath is ignored.

My original suggestion to you was based on the idea that the media was in your library, and the metadata had been corrupted, in which case I would have expected the current and older versions of your library to contain the same set of unique track identifiers which would have let that method work. If you have a new library made with the same set of media files all of the identifiers will be different. The FindTracks script in the post I mention above may work for you if the media files are those that were referenced by an older version of your iTunes database file. We're still no closer to working out how or why you have media in your library that you don't recognise.

tt2

Perhaps there are multiple tags that are out of sync, and iTunes is reading an empty one. I've found both MediaMonkey and MP3tag to be useful tools for cleaning up certain inconsistencies. Each track should have a single ID3v2.3 tag for best results on import to iTunes. Experiment with a small batch first.

tt2