Just a possibility, not a solution: check settings>general to ensure that this feature is set properly.

Your question does not differentiate whether you have 'new unread' or 'unread'. You mention they are still highlighted by which I think you mean bold font. That does not necessarilly mean they are 'new'. 'new' means new since you last selected the folder.

There is a difference between 'new unread' and 'unread'.

If a folder has received 'new unread': The folder will turn a blue colour to indicate this and font will be bold. When you select that folder, let's say it's the 'Inbox' - the 'new unread' emails should display a gold star icon at the begining of the 'Subject' and the font should be bold. If you do not read that email and select another folder - when you go back to the 'Inbox' that same email will now not display the star type of icon because it is no longer classed as 'new', but it will have a bold font to indicate 'unread'.

If folder only contains 'unread' but not 'new unread' then it will have a bold font which is either black or white depending upon whether you use a Light or Dark theme.

In the Folder Pane, it's possible to display two sets of numbers. The one closest to the folder name contains the number of 'unread' which includes 'new unread' and 'unread', the other number to the right is the total number of emails in the folder. As emails become marked as read the 'unread' count would decrease.

Emails will display 'unread' bold font until you open those emails to read them. Then, it depends upon your settings as to whether they get marked as read. If the auto select as 'read' is not enabled then you would need to do it manually.

• Either click on the small green dot in the 'Sort by read' column header
• OR right click on email in Message List and select 'Mark' > 'As Read'
• OR in Message Header click on 'More' > 'Mark as Read'
• OR use keyboard shortcut - press 'R' on keyboard

To set up auto 'mark as read' settings: In Settings' > 'General' scroll to 'Reading & Display' section If you want any unread mail to be auto marked as read when you open the email - whether that is via the 'Message Pane' or using a double click to read in a new tab:

• select the checkbox: 'Automatically mark messages as read'
• Select : 'Immediately upon display'

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