Hi,
I try Spire.Xls with large amount of data in single workbook. I have 50 sheets and more than 25 columns and 65,000 rows each. Spire.Xls throws exception. So, I create dummy excel file with 20 sheets, 20 columns and 10,000 rows each. And again, Spire.Xls throws exception "BIY is not valid named range".
I also attach the sample and pictures shows the error.
I hope I can retry your library as soon as you fix those erros.
Thank you