Title: ASP.NET: Flushing files to browser with Response.AddHeader() Slug: asp-net-flushing-files-to-browser-with-response-addheader Date: 2009-10-18 13:49:00 Author: Kartones Lang: en Tags: Development, ASP.NET, Troubleshooting Description: A guide on fixing content flushing issues in ASP.NET

This post should be nothing new for people used to ASP.NET 2.0 or higher, but at my last job I had to fix a summary download page that was not flushing correctly the content to the browser (it appeared as downloading the .aspx page instead of a csv file).

Probably because of the configuration of IIS, the content header was not being applied correctly with Response.AppendHeader(), so just changing it to Response.AddHeader() it was solved.

Response.Clear();
Response.ClearHeaders();
Response.ClearContent();
Response.ContentType = "text/plain";
Response.AddHeader("Content-disposition", "inline; filename=" + summaryFilename + ".csv");
Response.Write(summaryResults);
Response.End();

So, if AppendHeader doesn't work as it should, give a try to AddHeader.