As of this time of writings, scExcelExport component still not support Delphi 10 Seattle. Only Delphi XE8 will be able to compile the component without issue.
If you highly depend to this component, i will show you how to compile it in Delphi 10 Seattle (until the official release come out).
1. Open scExcelExportConfig.inc using text editor.
2. Add the code i have marked below inside scExcelExportConfig.inc:
{--------------------------------------------------------------------------------
*...