I have two XML files on disk. One is a Word file and the other one is an Excel file. From Windows Explorer, if I click on them, either Word or Excel is launched and I can access the file. But, if I use the following code to serve the file to the user in the browser, which makes use of the TransmitFile() approach, neither Word or Excel can open the file.

            lcFile = oApp.GetProcess("Transmit")
            oApp.oResponse.ContentType = "application/x-unknown"
            oApp.oResponse.AddHeader("Content-Disposition", "attachment;filename=" + lcFile)
            oApp.oResponse.TransmitFile(cCacheFat + lcSubDirectoryFat + lcFile)

It seems the browser is doing something to the file which makes it unreadable by Word and Excel. In Word, an error about an incorrect document syntax is thrown. In Excel, an unknown error is thrown. Can someone explain why I have no problem opening those XML files in Word or Excel from the Windows Explorer but can't from the browser?