Press Alt or F10 to restore the menu bar.

Press F8 to toggle the message pane. There is no such thing as a 'preview pane'.

I also abhor this useless feature! Unfortunately, unchecking the message pane is not a permanent setting. The pane reappears every time I turn on Thunderbird. If there is no such thing as a preview pane what is it called and how can I turn it off permanently? Thanks W

You already named it properly: it's called the message pane. http://kb.mozillazine.org/Window_layout_-_Thunderbird#Message_pane

When a message is shown in the message pane, the message has in fact been opened, not just previewed.

Are you using CCleaner? If so, make sure not to let it mess with Thunderbird settings.

Thanks for the reply. I'm not using cc cleaner. This started after an update. Somewhere there must be an option box to turn off this feature permanently, but no one seems to know where it is. I must turn it off every time under view, layout, message pane. I have no need for this feature. If I want to see the email i open it. If not I delete it. Having it take up half of my email page is a totally useless feature. Any suggestions

Thunderbird by default opens just like you close it. When this does not work properly it is usually caused by 3rd parry software like the above mentioned CCleaner. Try restarting with add ons disabled and see if one of those are causing the problem.

Thanks for the reply. It is quite discouraging to have to ask again. Restarting with add ons disabled does not help. The preview pane continues to appear every time I open Thunderbird, and can only be temporarily removed by unchecking preview pane in view, layout, preview pane. Someone who works on Thunderbird for Mozilla must know the answer and it certainly would be helpful if Mozilla occasionally reviewed these seemingly unanswerable questions. Thanks again for any suggestions, but this seems to be a bug in the recent update.

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