Windows 2011 Live Mail

I am operating my laptop with Win 10. I have been using Live Mail with no problems until the middle of this week, Wed or Thurs. I can no longer sign in. I keep getting a message to logon by entering my user name and password for the following server mail.talktalk.net, I have not changed my password to the best of my knowledge and there is no problem in receiving and sending emails with my email address on my other devices. I have spent hours trying to determine the cause of the problem but not being too computer literate I have reached somewhat of an impasse. Can anyone advise me on the course of action to take to resolve the problem bearing in mind I wish to continue with Live Mail as I have a lot of history I do not wish to lose and I find it very easy to use. I would like to see the password that is currently active in Live Mail, is that at all possible? Failing that I would like to know how to enter a new password without having to enter the existing unknown one of course.