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The reported exception is raised due to invalid workbook version. The default version in XlsIO is Excel97-2003. In that case, if you try to add 256+ columns, it will throw exception. We recommend you to assign it to Excel2007 or later. Please refer the below code snippets to avoid the exception. We have also shared a sample for your reference. Kindly refer to this and let us know if your issue is resolved.
//Step 1 : Instantiate the spreadsheet creation engine.
ExcelEngine excelEngine = new ExcelEngine();
//Step 2 : Instantiate the excel application object.
IApplication application = excelEngine.Excel;
application.DefaultVersion = ExcelVersion.Excel2010;
//If 2003 format file is opened and tried to add 256+ columns,
must be assigned
workbook.version = ExcelVersion.Excel2010;
Sample Link: Sample.zip
NOTE: This version settings doesn’t relate to the office version installed in the machine.
Please let us know if you need any clarification.
Thank you for updating us.
We have analyzed the given screenshot and found that data labels are visible and makes the chart unreadable, for which we suggest you to disable the data labels in the series by using the below code snippets.
IChartSeries series = chart.Series;
series.DataPoints.DefaultDataPoint.DataLabels.IsValue = false;
However, if you could share us the below information in detail, it will be helpful to investigate further on this.
1. Code snippets or the scenario you use that causes the program to stop working
2. What kind of formatting you are trying to apply and what is the output you are getting?
Please clarify us with the above queries and let us know if you need any clarification.