Help, I'm stuck - Most email notifications are lost

[armanic]

Hi,

I'm trying to get Mantis working for an open source project.
Mantis version 1.0.3a works OK. But, in most of the cases, the email notifications do not reach the addressees. I learned a lot about the various Mantis settings, but I'm stuck now. Is it a Mantis problem or what?

This is the current status:
- The check.php reports that the email is OK, but nothing is received.
- The email logging reports that the correct emails are sent to the correct addresses.
- Only one admin receives the emails always. Another admin does not receive anything.
- A developer receives only the email_notification_title_for_action_bug_submitted.
- New account emails to acativate the accounts are not received.

I do not know what to change ot test next to get this right. Any suggestions are welcome.