Assuming that Windows Live Mail is working correctly on your system, you need to set it as the default program for email. Go to Control Panel->Programs. Under "Default Programs", click on "Set your default programs". A dialog box will come up listing the various programs installed on your system. Scroll through the list until you find Windows Live Mail, click on it to highlight it, you will then have 2 options, "Set this program as default" and "Choose defaults for this program". The first sets it as the default for all file types it recognizes, the 2nd option lets you say which file types it should be the default for.