Exclude/Ignor a folder in the selected directory

I am a Windows user. MP3TAG is set to catalog the contents of the My Music directory. In that directory, there is one folder (with subfolders) that I would like MP3TAG to ignore -- to not search or display. How can I do that?

Try this filter:
NOT %_path% HAS C:\the path\to the folder\you want\to exclude\

Thank you, but I'm not familiar with filters. The path to the folder I want to exclude is:
C:\music\my music\itunes

So how is the the filter constructed, and where do I place it?

Read the documentation to learn about filters.

NOT %_path% HAS "C:\music\my music\itunes\"

The filters only function one at a time and only when filters are enabled.
Mp3tag keeps a drop-down list of previously used filters

If you mean by that that you can only define one filter criterion then I would like to direct your attention to the AND and OR operands.
These let you combine several filter criteria, e.g.
NOT %_path% HAS "C:\music\my music\itunes" AND %artist% IS Beatles
which would show all tracks by the Beatles which is not in the itunes folder.

No, I mean that only one filter expression can be active at any time.
AND and OR combine filter criteria into 1 filter expression.

But consider the Action Group dialogue.
Here we can execute any combination of check-marked actions with one click.
There is no similar functionality to select multiple filter expressions and apply them together.

And I'm not complaining, merely explaining.