IE fails with a download in PHP (seen when generating a CSV file)

Instead of prompting me with a dialog box to determine if I wanted to open the file or save, IE simply came back and indicated that it couldn’t save the file and presented with me with one option, ‘OK’. Of course ‘OK’ isn’t really ‘OK’, because it terminated the download and dropped me back into the website.

Very strange issue that happens on some systems but not others. The above blog post offers the most comprehensive discussion of this issue.

Link:
http://.../making-ie-accept-file-downloads/