<blockquote> We have multiple email address with the thunderbird under one account. </blockquote> I don't understand your terminology. Are you saying you do have multiple corporate email accounts with different email addresses, each with a different user ID and password? Or do you have a single account with one user ID and password but multiple email alias addresses? <blockquote> How do I get rid of second email address without deleting that address from our company thunderbird account? </blockquote> There is no such thing as a 'company thunderbird account'. You do have an account on your corporate mail server, and you use Thunderbird to access that account. If you remove an account set up in Thunderbird you won't be able to access that account anymore via Thunderbird. However, it does not affect the account on the corporate server.