I have been using Windows live mail happily for about three years. But about two months ago I saved an incoming email to a sub-folder, and then discovered that that e-mail had over-written all the other emails in that sub-folder. I thought it was just a glitch, but now it's happened in a couple of other sub-folders. I have full Norton anti-virus software, and that hasn't identified any bugs. Any suggestions?

Thanks

Steve