Tonight I noticed that several of my sites with flash were getting the error message “Click to activate and use this control” while being viewed in Internet Explorer (all is fine with firefox, opera etc).
The problem stems from a recent Microsoft Update http://support.microsoft.com/default.aspx/kb/912945/en-us This update has to do with the EOLA patent lawsuit that Microsoft recently lost.
As a work around I used the Unobtrusive Flash Object (UFO) from Bobby van der Sluis, replacing the standard macromedia object code.
This is going to start affecting A LOT of websites. As internet explorer users perform windows updates, sites that use flash will have this problem. It will be interesting to see how this plays out.