I have a large spreadsheet of filenames. I'm trying to break the
names into Filename and File extension using LEFT and RIGHT functions.
I'm having trouble getting some of these names because some of the
filenames contain more than one period,

eg., This.is.the.filename.DOC is in Col A.

Can someone suggest a function that would separate both parts?

This.is.the.filename in Col B
DOC in Col C.

Thanks in advance.