While I don't agree with the administrators who want to disable the reading pane for their users, it is possible to disable it using group policy in Outlook 2007 and up. Users of older versions of Outlook will need custom views to remove it and disable CommandBar IDs so it can't be turned back on.
Why it should be up to the user: Many people find they can work faster and more efficiently with the reading pane rather than opening messages, and the decision to use it or not should be left to each user. For the past, oh, 14 years, the reading pane is as safe as an opened message (if not slightly safer) because active content can't run in the reading pane. (See How Safe is the Reading Pane? )
I'm looking for a way to completely kill the reading pane and the user's ability to change the setting. The user cannot be able to change the view, etc. I have located most of the UI control numbers for the Office products but I haven't been able to locate the UI control number for outlook layout menu and the reading pane.
You don't need to disable each control; as I mentioned earlier, you can use group policy to disable the reading pane in Outlook 2007 and above. With the policy set, the reading pane is turned off and all reading pane options, buttons and commands are disabled.
When using the group policy templates for Outlook 2010 or Outlook 2013, look in Outlook > Outlook Options > Other for the Do not display reading pane policy object. In Outlook 2007's group policy template, it's under Tools | Options > Other.
If you prefer to set a registry key directly, create the keys and add the disablereadingpane value under the Policies key, set to 1.
Home and small office users can use the registry key too. As always, if the keys don't exist, you need to create them.
Do it for me
If you don't want to edit the registry yourself, you can use a ready-made reg file to set the key. Choose the correct file for your version of Outlook, download it and double click to run. (If your browser changes the file extension to .txt, you'll need to change it to .reg)