I’m afraid I was unable to reproduce this.
I tried using the latest version of GemBox.Spreadsheet and OpenXML SDK:
static void Main()
var path = "example.xlsx";
// Write Excel file with GemBox.Spreadsheet.
var workbook = new ExcelFile();
var worksheet = workbook.Worksheets.Add("Sheet1");
for (int r = 0; r < 50; r++)
for (int c = 0; c < 10; c++)
worksheet.Cells[r, c].Value = c + r * 10;
// Read Excel file with OpenXML SDK.
using var spreadsheet = SpreadsheetDocument.Open(path, false);
var rows = spreadsheet.WorkbookPart.WorksheetParts.First()
foreach (var row in rows)
foreach (var cell in row.Elements<Cell>())
Just in case, can you try again with the latest versions?
If the problem remains, please send us a small Visual Studio project that reproduces your issue so that we can investigate it.