Epplus not reading excel file
In the date of this post EPPLUS (v4.4.1) seems to handle xls files just like it does with xlsx:
Here is an example:
using (var target = new ExcelPackage(new System.IO.FileInfo("D:\\target.xls")))
{
target.Workbook.Worksheets.Add("worksheet");
target.Workbook.Worksheets.Last().Cells["A1:A12"].Value = "Hi";
target.Save();
}
also tested your code:
FileInfo newFile = new FileInfo("C:\\Excel\\SampleStockTakeExceptionReport.xls");
ExcelPackage pck = new ExcelPackage(newFile);
var ws = pck.Workbook.Worksheets.Add("Content");
ws.View.ShowGridLines = false;
ws.Cells["J12"].Value = "Test Write";
pck.Save();
System.Diagnostics.Process.Start("C:\\Excel\\SampleStockTakeExceptionReport.xls");
and it works without any issues.
Epplus does not handle .xls (BIFF8 format) files as far as i know.
It handles the newer .xlsx (Open Office Xml) format.
You can use excellibrary though as it works for xls files.