Version: Smartermail Enterprise Version: 16.1.6411
There seems to be a bug when accepting (unsure if also on declining) an invite sent via another Smartermail webmail user. It seems to append the domain name twice e.g. if the email is firstname.lastname@example.org it will try to send the accept notice to email@example.com@example.com.
You then get a delivery failure like so (and the recipient doesn't see as accepted on their calendar):
Could not deliver message to the following recipient(s):
Failed Recipient: firstname.lastname@example.org@example.com
Reason: The recipient does not exist
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