On a Windows Server 2008 computer that has IIS 7.0-only installations, you add the maxAllowedContentLength value. When you are running Windows SharePoint Services on a Windows Server 2008-based computer that has IIS 7.0, you find that you cannot upload files that are larger than 28 MB even though you have configured the large file upload settings. Usually, the error that users see is "The page cannot be displayed." In some circumstances, users may also see an "HTTP 404" error.
To work around this problem refer the following artcile