File with .msg extension not downloading

Question

I have the below code :

Dim filePath As String = Request.QueryString("FilePath")
    Dim fileName As String = filePath.Substring(filePath.LastIndexOf("/") + 1)
    Dim ext As String = Path.GetExtension(fileName)
    'If (ext = ".xls") Then
    '    Response.ContentType = "application/vnd.ms-excel"
    'ElseIf (ext = ".xlsx") Then
    '    Response.ContentType = "application/vnd.openxmlformats-officedocument.spreadsheetml.sheet"
    'End If
    If ext = ".msg" Then
        Response.ContentType = "application/octet-stream"
        'Response.ContentType = "application/vnd.ms-outlook"
    ElseIf (ext = ".xls") Then
        Response.ContentType = "application/vnd.ms-excel"
    ElseIf (ext = ".xlsx") Then
        Response.ContentType = "application/vnd.openxmlformats-officedocument.spreadsheetml.sheet"
    End If
    'fileName = Server.MapPath("~\\files\\RAP_Batch_Upload_form.xls")
    Response.AppendHeader("Content-Disposition", "attachment;filename=" & fileName)
    'Response.AddHeader("Content-Length", New System.IO.FileInfo(fileName).Length)
    'Response.AddHeader("Content-Length", New System.IO.FileInfo("Batch_test_11.xlsx").Length)
    Response.Redirect(filePath)
    Response.End()

I am able to download the files with .xls and .xlsx files but .msg files will give page not found error. The files are stored in an Attachments folder and a sample filePath looks like http://our.domain.com/Attachment/2017123456 Demo_Re.msg (Space is part of the fileName and for .xls and .xlsx files that is not a problem).

Could anybody tell me what am I missing.

Answer 1

Open your IIS, select properties for your website

Select HTTP Header -> click MIME types - > Click New and add ".msg" as extension and "application/vsd.ms-outlook" as MIME type.