A new feature in Office Groups (available in Office 365 Exchange Online) is the ability to use 'Send as' or 'Send on behalf of', just as you can for shared mailboxes.
Undo Send feature in Outlook on the Web
Outlook on the web's new feature: Undo Send. It gives you a few seconds (up to 30 seconds) to change your mind.
Office 365 Mailbox Size Increase
Mailbox quotas for E3 and E5 accounts is increasing to 100 GB, with all other Office 365 Exchange mailboxes remaining at 50 GB, including Business, E1, shared, resource, group and public folder mailboxes.
Enable Mailbox Auditing in Office 365
How to enable auditing on an Office 365 mailbox.
Deprecation of RPC over HTTP in Office 365 (and Outlook.com)
What exactly does the announcement that Microsoft is deprecating RPC over HTTP support in Office 365 mean for Outlook.com and Office 365 Exchange Online subscribers?
Direct Connect to Office 365
An administrator came to me with a problem: We are going to move to Office 365 and when we added our domain to the Office 365 portal and created the accounts, Outlook 2016 started prompting for the Office 365 login to reconfigure Outlook. We haven't yet changed our DNS records, we just created the accounts
Office 365 and Outlook.com: Interesting Calendars
A new calendar feature, called Interesting Calendars, is rolling out to Office 365 Exchange Online and Outlook.com users (on the new server). The current calendars offered are sports schedules.
Move and Resize Office 365 Launcher Tiles
Did you know you have the ability to move and resize the Office 365 launcher tiles in Outlook on the web? It works like it does on the Windows 8 or 10 Start page - simply drag the tiles to move them to reposition them. Click the 3 dots to expand the menu and select
Group Calendar Invitations
An Office 365 Exchange Online user had question about Group calendars in Office 365 and Outlook 2016. The user is sending invitations to the group and sometimes everyone receives the invitation while other times only some people get a copy. Note: this refers to the new Groups feature in Outlook 2016/Office 365 Exchange Online. Group
Coming Soon to Windows 10: Office 365 Search
Good news for Office 365 users, a future build of Windows 10 (available now in the new Windows Insider build), will restore the ability to search for email, appointments, and contacts in an Office 365 account outside of Outlook.