C1FlexGrid.SaveExcel missing method exception (.NET8)

C1FlexGrid.SaveExcel missing method exception (.NET8)

Posted by: andrea.davoli on 16 January 2026, 4:45 am EST

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  andrea.davoli

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  Posted 16 January 2026, 4:45 am EST

  Hello,
  
  i’m facing an exception when trying to save a C1.Win.FlexGrid.C1FlexGrid as Xlsx file with the method C1FlexGrid1.SaveExcel(fileName, FileFlags.AsDisplayed).

  Exception text: System.MissingMethodException: ‘Method not found: ‘Void C1.Excel.C1XLBook…ctor()’.’

  In a previous project with NET Framework 4.8 the method worked correctly.
  
  How can we solve the problem?

  Thank you.

• 

  uttkarsh.matiyal

  

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  Posted 19 January 2026, 2:41 am EST

  Hello,

  We created a simple sample with FlexGrid in .NET 8 but could not observe the behavior. Please refer to the attached sample for the same: FlexGrid_SaveExcel.zip

  The issue seems to be caused by an incompatibility between the versions of C1.Excel and C1FlexGrid being used.

  Could you please remove all existing ComponentOne NuGet packages from your project and then re-add them, ensuring that all C1 packages are on the exact same version?

  If the issue still persists after this, please update the attached sample or share a minimal, stripped-down version of your project so we can investigate the problem further.

  Regards,
  
  Uttkarsh.

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  andrea.davoli

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  Posted 19 January 2026, 4:07 am EST

  Hello,

  looks like it was actually a dll version issue.
  
  Now it works fine.

  Thank you for the assistance