For troubleshooting issues with Call ups not being sent out of your Exchange, please review the below article.

https://technet.microsoft.com/en-us/library/mt210446(v=exchg.150).aspx


If you are using ClickHome 3 with cloud based email service Exchange Online and you require to troubleshoot the receipt or delivery of a particular email to a supplier, the below article could be of assistance.

Troubleshoot email delivery using the Exchange Online message trace tool