Force Open/Save dialog with IE9+

Change the IE options to prompt for the save dialog
In IE9, Microsoft changed the way attachments are opened. A CSV (Comma Separated Values) file does not open the spreadsheet, but displays the content in a web page. A configuration setting allows you to change this behavior and always present the Save / Open dialog. This may not be the case in IE10, even with the 'MIME Sniffing' enabled, the 'Open/Save' prompt shows. In IE11 back to the displaying of the file.
It is understood that there are many more factors involved when it comes to the opening a default application. This article here tries to provide alternatives regardless of the additional software installed.
During my testing I started with IE9 on one workstation and the file was displayed in the browser. After upgrading to IE10, the Open / Save dialog was displayed. This case suggests that there is an inconsistency between IE versions.
If you are not sure how your version reacts, a small CSV test file is attached at the bottom.

Open the Internet Options from the IE menu.

> Security >Custom level ...

Scroll down to the Miscellaneous section and find the Enable MIMIE Sniffing.
>Disable the option.

NOTE: You may not be able to change this setting in a corporate environment. Your IT Department may have locked the Security options.

An alternative way to save the CSV file
Select the whole page content (Ctrl-A), then copy (Ctrl-C) the text.

Open the Microsoft Notepad application
>All Programs >Accessories

and Paste (Ctrl-V) the text into Notepad. Then save the file and make sure to terminate the name with the .csv extension. Notepad by default will save with the .txt file.

Now you can open the spreadsheet application.

Test File
Download To test your browser version, click the link to the left
and IE will either present the Open / Save dialog

or the CSV file will open in the browser
"Common Name","Latin Name","Weight in kg","Class"
"Horse","Equus ferus caballus",500,"Mammals"
"Raven","Corvus corax",1.5,"Birds"
"Atlantic Salmon","Salmo salar",10,"Fish"
"Snapping Turtle","Chelydra serpentina",8,"Reptiles"
"Carpenter Ant","Camponotus spp.",0,"Insect"
"Black Widow Spider","Latrodectus Variolus",0,"Arachnid"

Timestamp: 06/26/2017 04:53:05 AM EDT [on srv7cps]
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