Since yesterday I have been having a problem adding new calendar entries and replying to messages. I can open existing messages OK and new messages are arriving. I can see calendar entries but can't open them.  I can't send a new message if Live is already open but can if I use the drop down for Live Mail from the Start menu. The error message is always the same "A problem occurred while trying to open this message.

I have tried a few of the steps recommended in this forum:

1. Repaired Live Essentials

2. Defrag the message store

3. Uninstalled Live Mail and installed the latest version.

Nothing has fixed the problem. I have been running Live Mail on this laptop for over 2 years with no problems before this happened. Any suggestions?