# Change AAC file type to "Mastered for iTunes" **URL:** https://community.mp3tag.de/t/change-aac-file-type-to-mastered-for-itunes/45352 **Category:** Support **Created:** [May 6, 2019, 9:27am UTC](https://community.mp3tag.de/t/change-aac-file-type-to-mastered-for-itunes/45352 "2019-05-06T09:27:44Z") **Posts on this page:** 1 **Showing post:** 14
### Author: ![ohrenkino](https://community.mp3tag.de/user_avatar/community.mp3tag.de/ohrenkino/32/4843_2.png) [@ohrenkino](https://community.mp3tag.de/u/ohrenkino) #### Post date: [May 6, 2019, 10:50am UTC](https://community.mp3tag.de/t/change-aac-file-type-to-mastered-for-itunes/45352/14 "2019-05-06T10:50:36Z")
??? If you have a look at the list of fields in the help, then you will find that iTunes does not support all of them. So what should the update of MP3tag change in iTunes? Also, it is not certain, that iTunes saves all the information in tags or reads all of it from there as iTUnes maintains its own database. Apparently, there is a field shown as "Purchased by" - but see the thread about that field: > [@\[REQUEST\] iTunes Purchased By](https://community.mp3tag.de/t/request-itunes-purchased-by/15735): > > Can anyone make a script to edit the "Purchased By" field on iTunes? Thanks slight_smile Looking at the dump again, I see "MASTERED" as field (which is most likely a user-defined field - does that show in iTunes?) but your dump does not show a field called TYPE as it stops at TITLESORT... --- _[View the full topic](https://community.mp3tag.de/t/change-aac-file-type-to-mastered-for-itunes/45352)._