I have an application with lists of items and a pop up is used to change items in the database. Some of the items have attached files which have been uploaded.

Not too long ago I changed the application so the edit screen appears as a pop up window, rather than navigate back and forth to the list in a single window. This added a continuity to the application.

Unfortunately I'm not able to stream files to the desktop if the edit screen is a pop up window. If I go directly to the edit screen by entering a URL, files will stream OK. In another application I was not able to open a pop up window from within another pop up window unless I included <base target="_self" /> in the header. After learning that I always place that tag in pop up windows.

The sequence goes like this. The main page is opened and a list of items is viewed. One of the items is selected for editing and a pop up window appears for that. From within the pop up window an Excel spreadsheet is selected for viewing, but no open/save/cancel dialog appears.

To steam a file to the desktop the content type is set to unknown, content disposition is set to attachment and filename, then whatever bytes constituting the file are sent to the client. Following that the response is closed and server processing is ended. This is done rather than send a normal HTML page.

The browser used is IE 8. Can't use another browser in this instance. Help would be appreciated. Thanks