To enable notifications via e-mail, click on the slider in the gray box. It has to turn green. If the slider is green, it means that you will receive e-mail notifications.
Now, use the drop down menu to decide when you wish to receive your e-mail notifications.
Select spaces and topics for your notifications
You can now select which topics and/or spaces you wish to receive notifications of.
Click on the envelop icon to select or deselect a topic and/or space.
Do you want to completely reorganize your e-mail notifications quickly? Use the Select all button to select all spaces and topics. Now you can also use the Deselect all button to clear your e-mail notifications completely.
Microblog's "read" status - how it works
Should you have noticed that some digests don't reach your e-mail inbox, even though they should, then there is probably an explanation for this.
The Microblog doesn't differentiate between topics (or posts, for that matter) when it comes to the "last post read" status. The Microblog will always look at the very last post that you read and define every post (no matter if you actually saw it or not) before that one as "read", too.
Your Microblog timeline has 3 topics: Off-Topic, Finances and Meetings.
Your digest e-mail is set to arrive in your inbox at 11pm.
The whole day long, you read nothing in the Microblog whatsoever.
At 9pm, you read the newest post (let's say it had the ID #1234) - it was a post in the Finances topic.
The Microblog now marks every post up to the "ID #1234 post" as read. Every single one up to this very post. In all 3 topics. Even though you saw only one post in one topic.
Between you seeing that "ID#1234" post at 9pm and the digest being sent at 11pm, there was no other post made in those three topics. → You don't receive the digest, since the Microblog thinks that you read all available posts up to this point.