Error -54, "Can't back up iTunes Library"? What does it mean?

From an OS9 reference, error -54 is a software lock on a file or a permissions error. (Some of the old codes still apply to OSX although there is no formal list of OSX error codes.)

First, try simply restarting your computer.

Try quitting iTunes, then deleting the .xml (not .itl !) version of the library file in the iTunes folder (iTunes will generate a new one).

iTunes Library cannot be saved (Error -54) - https://discussions.apple.com/thread/1912814 - various things to try.

iTunes: Missing folder or incorrect permissions may prevent authorization - http://support.apple.com/kb/ts1277

Troubleshooting permissions issues in Mac OS X - http://support.apple.com/kb/HT2963

Hello

I had the same problem and it seemed to be solved by only restarting Computer

Mac OS X Yosemite on Mac Book Pro 2011

But as I saw your answer I tried to find this .xml file in the iTunes library and didn't find it (neither in the system Library neither in user library)

Is it because of Yosemite?

Thanks for your answer if any

Forgott to say I repair permissions first but it didn't seem to repair anything looking like iTunes

Constance