Gmail, Yahoo and other email providers switched to OAuth 2 and turned Basic Authentication off by default. When you log into the website to enable basic authentication, you are warned that it is a less secure login.
Messages are Marked as Read
Users are complaining that their email is being marked as read as it is downloaded, before they've read the messages.
Receive Reminders from Shared Calendars?
Copy events from a shared calendar to receive reminders.
iCloud Doesn't Sync
If the iCloud add-in is not syncing Outlook Calendar and Contacts, verify it is enabled in Options, Add-ins. You may need to edit the registry if it won't stay enabled.
Blocking Mail From New Top-Level Domains
How to block junk mail and spam sent from the new top-level domains in Outlook.
Always Warn Before Downloading Content
How to disable the ability to change the 'Warn me before downloading content when editing, forwarding, or replying to e-mail' option by setting a registry key.
Outlook Calendar & Variable Working Times
Setting the working hours in Outlook's calendar is a problem for anyone who works a mix of full and half days.
Outlook .HOL Error: US Election Day
The HOL file supplied with Outlook 2010 (and in the Outlook 2007 holiday update released in 2012) the 2016 US Election Day event is on the wrong date.
Synchronize Quick Access Toolbar and Ribbons?
How to save Outlook's Quick Access Toolbar or Ribbon customizations to use on another computer.
Category Colors Don't Display in Inbox
Category names but not the colors are displayed in the message list when the category column is moved.