“Package should contain a content type part [M1.13]”

Question

I am attempting to write to an Excel file however I keep getting the error:

Exception in thread \"main\" org.apache.poi.POIXMLException: org.apache.po

Answer 1

CHECK EXCEL FORMAT .... Firstly I created an sample excel with poi and I changed the columns with mine first attempt it give same error but after few try it successfully read .I wonder why it didn't worked first run :( but If you have right library please check the correct excel format