Step 1: All you need to do is open your file explorer, and go to: C:\Users\”your user name”\AppData\Local and copy the Mailbird folder that is there. Mailbird application should be CLOSED at the time of copying.
Step 2: Next, Install Mailbird in your new PC. After the installation is complete, go to the same location as the above, on your new PC and paste/overwrite the existing Mailbird folder with the back up that you’ve created from your old one.
Step 3: And that’s it! You can open and use Mailbird on your new PC with all your existing settings and email.