i just tested processing 30+ files (xlsx and csv)with a total of 20800 records

reading through ACE and writing datatable rows through the excel server/program and it took 3 minutes, before with jet reading the csv it took 7 minutes.....

i rearranged the code a bit though and put the files into a list of a class i built and automatically set all the queries and connection strings before the procesing, before i did that during processing, its so much cleaner with the class objects.