Testing out Dynamics 365 9.1 On-Premise and configurating a simple SMTP server (no authentication needed / anonymous + port 25) for sending out emails. Done exactly the same as I've done on version 9.0 so I am starting to think there might be something new to version 9.1 that I don't know of? There is nothing wrong with the SMTP server or firewalls, tested SMTP send via Telnet directly from the CRM-server and it works fine.
I activated Tracing in registry on the server to see if I could get any more error messages relating to this, and there is a few weird once:
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>Crm Exception: Message: Credentials must implement ICredentialsByHost for mailbox 00000000-0000-0000-0000-000000000000 in organization 02d92d4b-c0cd-eb11-bcec-005056a85101, ErrorCode: -2147220970
[Process:CrmAsyncService |Organization:02d92d4b-c0cd-eb11-bcec-005056a85101 |Thread: 31 |Category: EmailConnector |User: 00000000-0000-0000-0000-000000000000 |Level: Error |ReqId: 00000000-0000-0000-0000-000000000000 |ActivityId: fcb40a4b-6128-46dd-9eef-136a04f17b04 | EmailConnectorLogger.EmailConnectorTraceFormat ilOffset = 0x0
>MailkitSmtpOutgoingEmailProvider.Authenticate(SmtpClient): Error occurred trying to authenticate. Error Details: Unhandled exception:
Exception type: Microsoft.Crm.CrmException
Message: Credentials must implement ICredentialsByHost for mailbox 00000000-0000-0000-0000-000000000000 in organization 02d92d4b-c0cd-eb11-bcec-005056a85101
> at Microsoft.Crm.Asynchronous.EmailConnector.MailKitSaslMechanismProvider.GetSaslMechanism(AuthenticationProtocol authenticationProtocol, ISet`1 authenticationMechanisms, IMailboxDataProvider mailboxDataProvider, IEmailAccessConfiguration emailAccessConfiguration, ITraceHandler traceHandler, IFCBRetriever fcbRetriever, IFeatureControl featureControl, IOAuthTokenManagerFactory tokenManagerFactory, IOrganizationService organizationService)
> at Microsoft.Crm.Asynchronous.EmailConnector.MailkitSmtpOutgoingEmailProvider.Authenticate(IMailTransport client, IMailboxDataProvider mailboxDataProvider, IEmailAccessConfiguration emailAccessConfiguration, ITraceHandler traceHandler, IOrganizationService organizationService)
>-- End stack trace --
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