You're using the SMTP server settings you got with Office 365 and you get an error (like the following) when you try to send an email from Enterprise for Windows or your Birddog website.
Request: MAIL FROM: SIZE=114 RET=HDRS RCPT TO: ORCPT=Rfc822;Support@Birddogsw.Com DATA Response: 530 5.7.57 SMTP; Client Was Not Authenticated To Send Anonymous Mail During MAIL FROM [MWHPR22CA0056.Namprd22.Prod.Outlook.Com]
The problem is you're most likely using SMTP server "smtp.office365.com". That server can't be used for "direct send" emails. You need to use the server setting that contains "mail.protection.outlook.com". See the following Microsoft help doc: https://answers.microsoft.com/en-us/msoffice/forum/msoffice_outlook-mso_winother-mso_o365b/client-was-not-authenticated-to-send-anonymous/d405bcb0-f40c-42fa-b1b2-477597100123?auth=1
Do an MX Lookup for your email domain (use link below) and use the setting that includes "mail.protection.outlook.com".