Location of Flatfile used to load master data from BW into BPC

I need to know the location of the flat file which has been created via a package within a package link. The package link has a number of packages. the first 3 have worked successfully. However, step 6 - Export master data to Flat file and step 7 Import Master data from file. There an issue with the flatfile in step 6. We need to find this file in the file system. Could someone please inform us where these files reside ?