This is not a CSS problem. You must use the plugin MY SMTP WP.
Thanks for the reply but I think it was a misunderstanding.
The pluggin works great and sends e-mail to the recipients when I post via PHP.
The problem is that on their emails is WORDPRESS the sender. The recipients think it is spam!
I want it to be our name as a sender whick are “VÄSTERÅS TRÄDGÅRDSSÄLLSKAP”.
I have other pluggins install (Event Manager) that sends e-mail via PHP with our name as sender so I think it must be a way to cange it.
Sorry about my previous answer. Of course it fixed my problem with the plugin MY SMTP WP.