To help ensure that our automated emails reach your Inbox, BusyConf send emails using the Sender Policy Framework (SPF) and DomainKeys Identified Mail (DKIM).

What is the From: address for emails that the BusyConf application send?

Our emails are sent from support@busyconf.com, but we also set the Reply-To: header for certain emails so a reply goes to the intended party.

The Sender: header is support=busyconf.com@sendgrid.info. That email address isn’t valid, is it?

Actually, yes it is a valid email address. The equals character (=) is perfectly valid in the local part of an email address. Sources:

• http://en.wikipedia.org/wiki/Email_address#Syntax
• https://www.cs.tut.fi/~jkorpela/rfc/822addr.html (scroll to the bottom for “Lower-level syntactic constructs”)

Why do emails come from an address at sendgrid.info?

We use SendGrid for the transactional emails that come from our application. SendGrid cryptographically signs all of our emails with DKIM, which matches the sendgrid.info sending address. This allows a receiving mail server to verify the delivery was sent from who we say it was sent from.

Why is the sending server sendgrid.net?

Because SendGrid is delivering email on our behalf, we employ the Sender Policy Framework (SPF) for mail delivery to verify the sendgrid.net mail server. i.e We have DNS records that verify which servers are allowed to send email on our behalf. Combined with DKIM, this should override most spam filters.