This morning (11 October 2013) when I tried to create a new message using Windows Live Mail a small window appeared saying:-

A problem occurred while trying to open this message.

A problem has occurred. Please try again.

If I try to forward a received email the same message appears.

To send an email I have to log on to my BT Yahoo home page and send it from there, but this means that I do not have a copy on my computer.

I use Windows Ultimate 64-bit.