File Size Limits
Are file sizes limited in IronXL?
There is no file size or row/column limit in IronXL.
If you are seeing an error message regarding 65,535 rows this would suggest you are using an 2003-version XLS file.
The newer 2007-2010 XLS and XLSX version files have much higher limits.
Please see: https://support.office.com/en-us/article/excel-specifications-and-limits-1672b34d-7043-467e-8e27-269d656771c3#ID0EBABAAA=Office_2010