Assuming you have the settings as follows then Emails do not get marked as read until you open them.

check you have the following settings:

• 'Menu icon' > 'Options' > 'Options' > 'Display' > 'Advanced' tab
• select: 'Automatically mark messages as read'
• select: 'Immediately on display'
• click on 'OK'

Did you need to change the settings?

Hovering the cursor over an email in the list, but not clicking on it, will show more of the 'Subject' but this does not select the email, so it does not open nor is it marked as read.

There are different ways to open an email. IF the 'Message Pane' is enabled: Action: a single left click on email in list or using the up/down arrow keys on keyboard to highlight email in list. This will open email and display it in the lower 'Message Pane'. The email in the list will become marked as read and will no longer be bold.

If the Message Pane is not enabled, doing the above will have no effect. The email will not open and therefore will not be marked as read.

Do you need to enable the 'Message Pane' or is it already enabled?

To enable the 'Message Pane': 'Menu icon' > 'Options' > 'Options' > 'Layout' > select 'Message Pane' Note you can also toggle the 'Message Pane' view using the F8 key

If you double click on an email in the list this will open the email in a new tab or window depending upon what you selected in Options.

If Options settings are correct and Message Pane is already enabled and single left click (assuming you are right handed) opens in 'Message Pane' but email in list still remains marked as bold and 'unread', please tell the forum. When you say 'scroll through the e-mails on the main pane' please say what process you using. EG: mouse click, keyboard arrow keys, etc

Hi Toad-hall Thanks for that it did resolve it also I had a new update to complete so that helped. Thanks for your help

I have the opposite of this problem (Kind of) When I delete an email above one that has not been read, it automatically marks the unread message as read. I have checked my settings every time this happens. They are always set to 'Automatically mark messages as read' AFTER displaying for 10 seconds. I restart TB and everything is back to normal... for a while. Then after a few days it starts all over again.

Any suggestions?

Hi thejug You do not have the same issue as posted by the original postee of question. This question has already been marked as solved. When you post a comment in another persons query, you are asking that person to offer help. They may not know the answer or may not appreciate getting unwanted irrelevant emails. The only reason I got an email was because I forget to stop following this solved question. Please post a new question clearly staing the issue. Please state what OS you use and what version of thunderbird.