I need to find how many instances of a certain phrase occurs in a set of excel files in a directory. (for example, looking for the word "sample" where there might be 3 instances in one .xls file, and 7 in another..) I can't seem to find the right filters in the explorer window.

Hi
You won't find the right filters as what you are trying to do in explorer is not possible. All it will do is display the files containg the words or phrases you are looking for. It will not count the number of instances in each file. You would probably have to write a macro to do this.
OTPM