Problem This error can occur at startup and is caused by incorrect Viewtab settings. It can appear in any build but is caused either by moving the Viewtabs to the bottom of NEO, or attempting to undock the last View tab (typically Search view). The latter problem was introduced in Beta Build 284, and has been fixed in the Release version of NEO or NEO Pro. So on beta versions, please refrain from undocking the last tab in the Viewtab.
Even if the build you have includes the fix for the cause of the problem, you must follow the steps below to repair it.
Resolution The following steps allow you to start NEO in a special way that resets your user interface settings such as toolbar locations and windows size. It does not change the options you have set in your Options, nor does it change any information related to your messages or NEO folder properties.
Close NEO and Outlook.
Ensure you are using the latest version of NEO or NEO Pro. The following steps will not work with builds previous to 270.
Restart NEO by holding down the Ctrl and Shift keys when double-clicking the NEO or NEO Pro icon on your desktop. Keep the keys held down until a confirmation message appears.
Follow the instructions in the confirmation message.
NEO or NEO Pro will then continue to open with these elements reset to their defaults.