If you still get the exception, please provide us your sample code and source xls/xlsx file replicating this issue, we will look into it and help you asap.
I have looked into this issue and found that the error/exception occurs because of the following commented line. It seems like you are trying to add some invalid characters i.e cb.Text
Please see the following sample code, it works fine. I have added some other valid text now. I have attached the output xlsx file also.
Please also see the screenshot for your reference.
C#
Workbook wb = new Workbook();
wb.Worksheets.Clear();
int i = wb.Worksheets.Add();
var ws = wb.Worksheets[i];
ws.Name = “New”;
var index = ws.CheckBoxes.Add(10, 2, 20, ws.Cells.GetColumnWidthPixel(1) + ws.Cells.GetColumnWidthPixel(3) - 5);
Aspose.Cells.Drawing.CheckBox cb = ws.CheckBoxes[index];
//cb.Text = “Location 1 ([%¤#!#%&!§§!#¤HELLO)”;
cb.Text = “Some other text”;
cb.Font.Size = 10;
cb.TextVerticalAlignment = TextAlignmentType.Center;
var hideCell = “B” + (10 + 1).ToString();
ws.Cells[hideCell].PutValue(“LnkCell”);
cb.LinkedCell = hideCell;
cb.Value = true;
cb.LineFormat.ForeColor = Color.Orange;
cb.LineFormat.Style = Aspose.Cells.Drawing.MsoLineStyle.Single;
cb.LineFormat.Weight = 2;
wb.Save(@“Result.xlsx”, SaveFormat.Xlsx);