//This gets rid of the exception but we should not remove all the names
//currentWorkbook.Worksheets.Names.Clear();
var b1 = userWorkbook.HasExernalLinks();
//This does not helps. Furthemore, both b1 and b2 are True...
userWorkbook.RemoveExternalLinks();
var b2 = userWorkbook.HasExernalLinks();
mainWorkbook.Combine(userWorkbook);
MemoryStream ms = new MemoryStream();
//This causes the "Object reference not set to an instance of an object." at Aspose.Cells.ExternalSheetCollection.FindSupbook(Int32 refIndex)...
mainWorkbook.Save(ms, SaveFormat.Xlsx);
The files being used are attached. Please see the comments in the code. 2.xlsx contains a number of external references (names). .RemoveExternalLinks() does not work in this case. Before and after .HasExternalLinks() method returns True. Anyway, I think there should be no exception in any cases.
Could you please look into it asap as we experience the issue in production.
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