Hi, In BackEnd, I see we have file "...ExcelExporter.cs" (define method ExportToFile). And service file "...AppService.cs", we use this method - ExportToFile (Stream File saved TempFileCacheManager) Afterthat, in FrontEnd (Angular) we call method Download from Cache. My question is, Why complicate so many steps? Why use caches here? Why don't we download it directly from the stream NPOI? Thanks.