If I enter a user with the people picker or if I use a SharePoint group the mailing is possible.
However if I want to send an email to an active directory (security or distribution) group. It does not work.
An user lookup from a list does also not work. I receive the error " Failed to send notification. Cannot get the full name or e-mail address of user "#DisplayName". Always there is an hash before the display name, so that the name cannot be resolved (not found).
Does somebody know a solution about this?