The wait was just a futile troubleshooting attempt.
Thanks to all who provided input regarding structure of the
code - rather than the placement of files.
The structure as it stands is designed to read more than one file if applicable - so the loop you may be referring to is a loop that should indeed close each worksheet prior to beginning anew.
I don't experience this problem on my pc - leading me to believe that the recommendations regarding updating perl surely would help. Unfortunately don't have the option of a blanket update of the various user VDI environments where the code will need to function - or rather the time to accomplish that task.
I'll try revising the sequencing of application and workbook calls to see if that helps. I really dont want to manipulate any values within the spreadsheet, only read them and then use ODBC to write to and update DB records.