...
A 'typical' SPF record will be similar to this example:
"v=spf1 a mx include:authsmtp.com -all"
Verify the update was successful by going to https://mxtoolbox.com/spf.aspx, entering your Domain Name and selecting SPF Record Lookup. When your Domain details are displayed, check for entries in the "Type" and "Value" columns that indicate Type "include" and Value "authsmtp.com".
Authorize b4 to send from your email addresses
All email addresses under your domain that you wish b4 products to send emails FROM on your behalf must be authorized by you in our mail server. You provide your authorization to us through authSMTP.
When you provide us with any address you wish us to send from, we enter that address into our account at authSMTP, which triggers an email TO that same email address. The email advises whoever monitors the email address you provided that
...
steve@b4checkin.com is requesting your permission for authSMTP to send from the address.
Here is an example of the request.
...
To provide your permission, follow the click-through instructions in the request.
...