You can see from the Custom Settings in the profile that it is modifying Google Chrome–and probably other stuff too, had we scrolled down a bit.) Nicely, it shows the date installed at the top, which should correspond to when you started having problems sending mail.

(You might notice that the name of this profile– StandardBoost– is listed in the Malwarebytes report. If you go to System Preferences (under the Apple menu) and you see a button called “Profiles,” click it and see what you get. For an individual, a Profile is bad news, almost certainly a sign of malware, and should be removed. It’s easy to see the value profiles provide to a big company, especially when it comes to restricting the changes a user can make. Importantly, a profile prevents the user from making changes to those settings. IT departments sometimes use Profiles to control various aspects of the Macs that they manage: they can specify the home page, the search engine, and many other options. Malware will occasionally put a “Profile” into your System Preferences. And then run Malwarebytes again as soon as the Mac is back up.)

(Malwarebytes may tell you that a restart is required, and if it does, restart right away. If Malwarebytes shows you such a list, click the blue “Quarantine” button at bottom right, and you’re done.

Malwarebytes apple