I am facing some issues with the mail function for invitations since Yii was introduced. Emails sent are not delivered within the company but I can send mails to my external address.
Testing the PHP installation both with HTML and plain-text mail() succeeded, so there is no general rejection of mails from this server.
So I assume there must be something suspicious with the headers limesurvey uses, making the company server block the messages.
Removing the custom header from controllers/admin/token.php did not help.
Any ideas?