Please help us help you and fill where relevant:
Your LimeSurvey version: LimeSurvey Community Edition Version 6.1.8+230717
Own server or LimeSurvey hosting: own server
Survey theme/template: vanilla & sea green for admin
Plugins used: LDAP
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Dear LimeSurvey community,

is it possible to configure our own limesurvey instance to verify the authenticity of the senders mail-address with our own mail server? LDAP is already implemented and functionable.
Currently it is possible to send mails from "non-existing" mail accounts. E.g. below:
M.Mustermann@example-university.com -> would be verified and sent
iAmANonExistingMailAdress@example-university.com -> would be deemed non existing and mail will be dropped

At the moment both mails would be send without further verification.

Thanks in advance!