RE: From where i can check my undelivered Mails
For those Who wants to check Email Functionality with Dynamics 365 Online versions,
This might help you :
How to Setup Microsoft Office 365 and CRM Online Trial Outlook Client
Use this URL for trial out for Office 365 Enterprise E3 Trial - 1 month term
"[View:https://portal.office.com/partner/partnersignup.aspx?type=Trial&id=9155365f-1f28-4dc9-afc8-7038c14d970c&msppid=3009636:750:50]"
Then login to the Microsoft Office 365 Portal using the same Administrator login created from the CRM Online Trial. Navigate to “Purchase Services” and request the “Office 365 Enterprise E3 Trial”
Use below URL
[View:https://mscrmonline.wordpress.com/2014/02/13/how-to-setup-microsoft-office-365-and-crm-online-trial-outlook-client/:750:50]
In the end you need to set setting in CRM trail version for which you can use this URL
[View:https://blogs.technet.microsoft.com/ptsblog/2011/03/14/sending-e-mails-from-microsoft-dynamics-crm/:750:50]