Thunderbird is an Email client software system and you can work with it within the following method.
1. Open Mozilla thunderbird.
2. within the left panel you’ll see a list of your email accounts. Double Click on “Inbox” or if its hidden, click on your email, and it’ll expand and show the inbox, the trash list. etc.
Another choice is to right click on the e-mail and click on on “Get Messages”.
Thunderbird also automatically checks email each five to ten minutes. It also checks mail automatically when you open the program.