My husband and I have the same e-mail address. His is on an old 2001 platform. Mine was on this platform but in late 2011 my computer didn't like this. I took my computer to a repair shop and the technician installed Thunderbird on my computer. Thunderbird had been working fine until this spring when he was with a friend. While he was surfing the internet, in order to do what he wanted he needed to change the password to our e-mail address. He did this with success. I texted him for the new password. I entered this on my computer and was able to access our e-mail on Thunderbird. About a week later this password did not work. I was able to receive e-mails but was unable to reply to e-mails or send out new e-mails. What do I need to do?

Many thanks!!!