Symptoms

The X-AspNet-Version header is exposed, its value reflects actual .NET version of the Office 365 Application Endpoint.

Cause

This header is exposed by default.

Resolution

Feature Request #PFR-1254: "Office 365: Hide the 'X-AspNet-Version' response header on the Endpoint side" has been addressed to Odin Development team in order to implement such functionality.

Manual workaround:

Add the following setting to the system.web section of the web.config file:

<httpRuntime enableVersionHeader="false" />

and restart the IIS service.

Internal content