When I try to send e-mails with Live Mail, they go to the Outbox, and sometimes are sent after some hours and sometimes not.  If I try to re-send them, the Live Mail status window (with the "Tasks" and "Errors" tabs) replaces the Live Mail window, indicating under "Tasks" that it is "executing" the attempt to send the e-mail, but the only way that I can stop it and get the main Live Mail window to open is to re-start the computer.

It may be coincidental, but these problems started when I received a message from Comcast to change the password for access to my Comcast web mail.. I did that, and entered the new password in the appropriate place in my Windows Live Mail controls.  As I said, Live Mail sometimes receives and sometimes sends e-mails, but not reliably.