SMTP, or simple mail transfer protocol, is the standard way to send email (also referred to as outgoing email). SendGrid provides a solid SMTP service so you don't have to host your own email server.
You don't need to worry about setting up SMTP if you are also using OneOffice Productivity, unless you intend on running marketing campaigns -- which you must use a dedicated service for.
OneOfficeERP comes built-in with a configured email client so that you can send and receive emails in OneOfficeERP and append to documents if required.
SendGrid’s SMTP API allows developers to specify custom handling instructions for e-mail using an X-SMTPAPI header inserted into the message.
You need to create an API key to authenticate your application. In this case, OneOfficeERP. Learn more about integrating SendGrid with SMTP here
Once your API key has been created, you need to configure it in your OneOfficeERP account > Create a New Email Account.
Email Address: Your Email Address
Email Login ID: API Key [API key generated in Step 1]
Password: Your Password
Service: Select "SendGrid"
Now save this information and you have successfully configured the SendGrid SMTP Email in OneOfficeERP.