Step Wise Manual 3mail mail settings for thunderbird
If you don't have a 3mail mail address. you can create an email id from here then you can 3mail email login.
Open Thunderbird Software App. Click on Email
When you click on the email, pop-up Set UP an Existing Account Screen.
Enter Your name, 3mail Email address and Password then press Continue.
Click on the Manual config menu at bottom.
Enter Below 3mail incoming server settings.
In incoming click on the dropdown menu and select IMAP.
Add server host :imap.tre.se
Port: 143
select SSL/TLS
Enter Below 3mail outgoing server settings.
In outgoing select SMTP.
Add server host :smtp.tre.se
Port: 25
select SSL/TLS
Tap on Done. Now you are ready to use your 3mail email account on your Thunderbird.