



To resolve this behavior, use one of the following methods, as appropriate for your situation. By default, the earlier version of Outlook is removed because two versions of Outlook cannot coexist. The 20 versions of the Office programs, except for Outlook, are installed to coexist with earlier versions of the Office programs. However, the earlier version of Outlook is removed. If you select the option in the Setup program to keep all earlier versions of an original release non-trial version of an Office suite, the earlier versions of the Office programs are not removed. This behavior occurs because two versions of Outlook cannot coexist. This behavior occurs even though you select the option in the Setup program to keep all earlier versions. If an earlier version of Office is currently installed, and the option to keep the earlier Office version is selected, the earlier version of Microsoft Office Outlook is removed, and Outlook 2007 or Outlook 2010 is installed unexpectedly. For a side-by-side installation, you install an original release non-trial version of one of the Microsoft Office 2010 suite or the 2007 Microsoft Office suite or suites that are listed in this article.
