You had better use Gmail, not Yahoo or Hotmail.
1. Connect NVR to the router by ethernet cable? Pay attention: there are 4 ethernet ports at the back of NVR which includes 3 LAN port and 1 WAN port. Please use WAN port to connect the router, not LAN port.
2. Check P2P status and make sure it is online.
3. Go to System setup-Channel setup-Video detection. Enable it and tick Email Notice option.
4. Please log in your Gmail account.
5. Please open website below
6. Please tick turn on.
7. Please set up email in DVR setting like the picture below. If the mail test succeeds, it is working.
The SMTP server is smtp.gmail.com
the port is 587 or 465.
the user name is your Gmail account
password is your Gmail password
the sender is your Gmail account
the sender is the receiver and can be any email