Wow, that was interesting (Email plumbing)
We were having issues with our email invoices getting marked as spam or simply deleted by mailservers with no notice; subscribers weren’t receiving their invoices. After a lot of troubleshooting we figured it out.
Net253 shares office space with Helldyne Inc, which is Steve’s Electrical Engineering firm. Our faithful bookkeeper, Janet, uses a PC which has 2 sets of books on it. When the invoices are “batched” for the month, they would queue up and get ready to be sent from her Outlook mail client. That’s the background.
We added a feature to our net253 website which enables home users to subscribe to an email alert list. The list allows us to send you service alerts in case there is something big going on, like an emergency repair of the network because Rocky the Seabeck Squirrel decided to put more fiber in his diet.
We use Squarespace to host the website. We had to adjust our email SPF record to allow both Squarespace and 1and1 (our email service) to be allowed to deliver emails from net253.net. When we made that update, we changed a -all to a ~all. (dash to squiggle). This causes any email that somebody spoofs as net253 to show up marked as spam.
Back to Janet’s PC. Her outlook account only had her Helldyne email; we used slight of hand to forward accounting@net253.net to accounting@helldyne.com. In retrospect that was a really dumb idea on my part, but it was expedient at the time 5 years ago. When Janet sent out the invoices, they went thru the Helldyne email server which then delivered our email to your email providers such as Apple/Google/Yahoo/Microsoft. Their system would look at our SPF record for net253.net and immediately, correctly, mark our email as SPAM. Gack.
We reconfigured Janet’s PC have both Helldyne and Net253 accounts in Outlook and tweaked our SPF record so any mail not from Squarespace or Helldyne or 1and1 mail servers is silently deleted.
That is a way too much detail rant on what goes on to get email delivered.
Bottom line, we fixed it.
-Steve