I have a “task assigned” alert email generated from a SP 2010 Foundation site. The email contains a link to the document on which the task is assigned. The document file name contains spaces (e.g. my document.docx). When I click on the document link on a PC with IE7, the URL is encoded to replace the spaces with %20 and the document is displayed. When I click on the document link on a PC with IE8, the spaces are removed from the URL and the document is not displayed. I instead get a 404 error because the document cannot be found.

If I modify the URL directly in the browser to insert the spaces in the correct place, the document is displayed correctly.

What are the SP 2010 or IE8 settings that will enforce the URL to be encoded?