When Accelo was younger, we had a lot of clients who were still using legacy mail servers (simple POP3 type setups with their ISPs.) While there are still some clients using this configuration, for the vast majority of folks GSuite or Office365 are much better ways to deliver affordable and powerful email, calendar, file storage, and more for their small business.
In addition to our clients changing the way they use these systems, systems like GSuite and Office365 have seen dramatic improvements over the years, with new features like Content Compliance (Gmail) and Transport Rules (Office365) allowing our users to undo/unwind some settings they might have been using to make sure Accelo gets copies of their emails for our powerful (and popular!) email tracking feature.
In short, anyone who's using Accelo as their outgoing email server (using either our SMTP feature or GSuite's Outbound Gateway) should change their settings to send email directly and bring a copy into Accelo.
Why? In short, it is related to one of the problems with cloud services: they're so easy to get started with and since you pay by the minute, there's cases of spammers using cloud services and big email providers (like Microsoft through both Office365 and Hotmail) are protecting themselves by blocking cloud servers (like Accelo's hosted with Amazon Web Services on EC2) from sending emails to Microsoft-run email accounts.
Below are the changes or things you'll need to consider for the three main ways people have used Accelo to send emails out from their users.
As always, if you have any questions please email firstname.lastname@example.org.
While "incoming" emails received by you and your colleagues in GSuite can be forwarded directly to your own capture account (eg, email@example.com) through filters/rules, there isn't a way for individual users to configure capture of their "outgoing" emails into Accelo.
While Accelo provides an API-connection to "pull in" sent emails, this feature isn't real time (we have to go and check-in with Google's servers regularly) and so administrators have preferred to set up their GSuite account so that Gmail would send all emails out via Accelo's servers, allowing us to be part of the real-time tracking of sent emails.
A few years ago, the only way to get outgoing emails into Accelo in real time was to use the Outgoing Gateway feature (accessed via the Gmail Advanced settings in GSuite, e.g. https://admin.google.com/YOURDOMAIN.com/AdminHome?#ServiceSettings/service=email&subtab=filters (replacing YOURDOMAIN.COM with your actual domain.)
This Outbound Gateway method is no longer recommended - we instead recommend removing your Accelo domain from here and instead using Gmail's newer Content Compliance feature.
The Content Compliance section is further up on the same screen, and allows you to create a "rule" at the domain level to do things like BCC emails. This is exactly what you want to do instead.
Exchange, and now Office365, are products with a longer enterprise history, so features mandated by regulations like Sarbanes-Oxley for retaining emails have been available for quite some time.
As a result, it is unlikely we have many users who are using Accelo as the outgoing email gateway (or relay in the parlance) for their Exchange/Office365 configuration. However, if you are doing this you should change your settings to either send emails directly or use your ISP provided outgoing email server.
There's some bad news and some good news here.
The bad news first. There really isn't a way to continue using Accelo as your SMTP server and have a high degree of confidence that mail providers like Hotmail/Office365 won't block email delivery (we can't control what they do unfortunately.) While we aren't going to be turning off this feature imminently, it is something we'll be deprecating (hiding) soon and then turning off next year. You're going to need to change your SMTP server to be your ISP or hosting provider.
The good news second. You can now set up autobcc'ing from most major email clients now. We only introduced the SMTP relay feature because email clients like Outlook and Thunderbird could not do this before - but they can now!