Since this is a very irritating problem, we've listed the solutions first. If you'd like to understand why this issue occurs, you can read about it here.
"Spam Reporting Address"
If you've received the error message "Spam reporting address", please read this article.
We recommend trying a variety of these solutions to resolve the problem.
Pay special attention to the subject line - Remove any special characters that are not absolutely necessary, including but not limited to
Send the message without the attachment - If the message is delivered correctly, you'll know the attachment caused the spam filter to flag the original message. See number 4 below.
Adjust the number of recipients - If one or two emails generate an error, try resending the message just to those email addresses. If the message goes through, you'll know their email provider was preventing the delivery because of the large number of recipients.
Why does this happen?
The short answer: special characters in the subject of the email (such as + or &), the number of people the message was sent to, whether or not there are attachments, and the email provider of your and your colleague's email addresses impacts whether or not an email is delivered to the inbox, the spam folder, or not at all.
The long answer:
No one likes spam emails, so email providers have a vested interest in reducing the amount of undesirable junk emails that land in your inbox. However, each email provider - Google, Microsoft (including Hotmail and Outlook), Yahoo, Apple (iCloud and others), and private company emails - all have their own definition of what constitutes spam. There is no industry-wide definition or set of protocols. This is partly due to a lack of regulation and partly due to business competition - you want to be seen as being tough on spam, so you adjust your protocols regularly.
With a service like SetKeeper, the emails go through a third party sending service before they land in your inbox. All email providers have some kind of filter that is activated when it receives third party messages like this, because spammers are more likely to use these types of services to reach the largest possible number of inboxes. So while it's great that it keeps spam out, it is irritating because it also might keep SetKeeper emails out.
This would also explain why sometimes the emails are delivered correctly and sometimes they're not - the filters are very sensitive and sometimes a message with an attachment goes through just fine, and sometimes it gets flagged because there was a "&" in the subject line. It's also much more likely to land in your inbox if your production office sends the message just to you - 1:1 communication is less suspicious to the filter than 1:100 communication.
Still no luck?
Please contact firstname.lastname@example.org if you need further assistance.
Happy Filming! 🎞️