If you are a Small Business Server 2008 or 2011 user, you have Internet Explorer 9 installed on your server, and you try to close the Exchange Management Console, you may encounter an error similar to the one listed below.
You must close all dialog boxes before you can close Exchange Management Console
Microsoft has released a fix for this issue and I’ve included the download links below. In order to install this fix, you must have the latest updates installed from Microsoft Update as of October 11th, 2011. If you have not updated your server(s), do so before installing this patch.
If you are not experiencing this issue, it is advised that you don’t install this patch, as it has not been as thoroughly tested, and is planned to be rolled up into a future Internet Explorer update.
For Windows Server 2008 / Small Business Server 2008 systems – click here
For Windows Server 2008 R2 / Small Business Server 2011 systems – click here
Microsoft Knowledge Base Article #: 2624899