Case of the SAP ‘Do you want to open or save tx.sapssd?’ on IE9

The component that was broken was advanced reporting functions that hook into the SAP GUI. Although this worked fine in IE8 on IE9 users were receiving a message “Do you want to open or save tx.sapssd from sap url?

A quick search of this prompt found many people experiencing this same issue on earlier versions of IE when file registration was configured for the extension .sapssd. There was no file registration information for this extension, and re-installing SAP GUI didn’t make the error go away. So I wondered what is the IE8 and IE9 version doing differently?

I created the following registry key to register the MIME type to the CLSID I had found earlier:

Windows Registry Editor Version 5.00
[HKEY_CLASSES_ROOT\MIME\Database\Content Type\application/vnd.sap-gui]
"CLSID"="{83658045-6571-3232-7082-797884697869}"
"SapCreateKey"=dword:00000000

After adding this key I immediately refreshed IE9 without restarting:

and instantly SAP menu is back alive & kicking!