You had better use gmail, not yahoo or hotmail.
Pls refer to these steps below.
1. Please confirm recorder has connected to Internet successfully. You can go to the picture below to check it. If it always keeps disconnected or shows probing DNS, please click here to get some help. /kb/content/10/87/no36-what-to-do-if-dvr-or-nvr-can-t-connect-cloud.html
2. Please Enable alarm and tick the 'Send Email'.
3. Please log in your gmail account.
4. Please open website below.
5. Please tick turn on.It's very important.
6. Please set up email in recorder setting like picture below.
If you click 'Mail testing' shows Test success, it is working.
'Smtp server' is smtp.gmail.com
'Port' is 465
tick 'Need SSL'
'User Name' is your gmail account
'Password' is your gmail account password
'Sender' is your gmail account
'Receiver' can be any email that you want