Here is the scenario:
Logged into a Windows 7 Enterprise SP1 computer with Internet Explorer 9, behind a proxy (squid I think, though not set up by our organisation) which uses current Windows credentials without prompting.
The user goes through the following process:
- Visits a website and tries to download an Office (2010) document
- IE9 brings up dialog box asking user to open/save.
- User clicks open
- The user is prompted to enter credentials for the proxy
- User presses escape or enters credentials
- The document opens
So, it is apparent that the credentials are not required. But IE9/Office asks anyway. Often this prompt is behind the browser so the user doesn't even know they need to do anything. This doesn't happen if the document is saved first, or in Firefox. I've also disabled on-access scanning in our anti-virus solution.
I have read quite a few things on the web regarding Sharepoint prompting, but none to do with proxy. Most of the solutions relate to "Local Intranet" sites or sites under the organisation's administrative control (mainly IIS related).
I have managed to avoid this scenario by explicitly naming a site in the proxy bypass list, but of course it is neither possible nor viable to do this for every site on the web!
Does anybody have any experience with this scenario?