Ignor list do not work with *.pst

I have a sync with 2 PST files. During sync I always get error messages that the pst-files can not be synct. OK when Outlook is open, nothing can get access to the pst-file.

Ich put *.pst in the ignore list:

But this does not work. The error messages still occur.

Only if I uncheck the directory with the pst-files no more error messages will be displayed.

Is the syntax in the ignore list wrong?