ActiveX - computer has stopped allowing me to play msn games as it does not recognise the publisher

my laptop has just (for no obvious reason) stopped me from playing msn games eg bedazzled etc. It says I don't have ActiveX but will not allow me to download the ActiveX as it doesn't recognise the publisher. It is probably all about my security settings - however I dont really know why they would have changed as it was all working OK a week ago. Can anyone help?