I am trying to add an ISRC column and go to add ISRC through the Extended Tags drop down. As you can see from the attached image when I choose to add it the "Okay" button is not functional.
Help?
Could it be that you have to enter some content (in the box below ISRC) first?
The reason:
You can not add new "empty" fields.
The fields exists either WITH content or they don't exist at all.
You need to include a value there before the OK button will be active.
If you simply want to create a new column without setting a value first, use the View>Customize Columns method instead. You can create as many new columns there as you wish, and assign which tag values or functions you want.
These are two different things:
a) Columns (visible in the Excel style table called "File List")
b) Extended Tags (showing the content of every selected track)
What exactly do you want to add?
A new column or a new ISRC field in the track?
Hi! A new ISRC field in the track.
It gives me the ISRC option under Extended Tags but won't let me "OK".
Okay. I get what you were saying. So I added the ISRC code for the song in question and the "OK" became functional. I don't see it in the file listing, though. When I hit Command T it's there. But I'd feel better if I could see it in the file listing as well.
Then just follow the already linked instructions to add a new (ISRC) column:
BTW:
If you use a Mac you can read the instructions here:
Thanks!!! It's working!!! 
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