Using Gmail SMTP Interface for EMail

GMail SMTP (Small Message Trasfer Protocol) servers provide the means by which third party systems can send EMail messages using a GMail account. However, there are some important details to be aware of:

• Google limits the number of recipients in a single EMail, and the number of EMails that can be sent per day. The current limit is 100 recipients for a single EMail.
• On reaching the threshold limits, users will not be able to send messages for the next 24 hours. Once this temporary suspension period is over, the counter gets reset automatically, and the user can resume sending EMails.
• By default, third-party applications are not allowed to send EMails using your GMail account. Hence, there are few settings that need to be addressed by the user.
  

How To Enable SMTP EMail Sending In GMail?

1. Before sending EMails using GMail's SMTP Server, you will need to go to the security and permission level settings under your Google Account Security Settings.
   
   
2. Make sure that 2-Step-Verification is enabled.
   
   
3. Create an application password for your application or device.
   
   

If you would like more details, please consult Using 2-Step verification with GMail

Note: Although changes are usually processed immediately, it may take an hour or more to reflect any security changes