Microsoft Outlook is one of the most popular desktop email clients among Windows users. In Outlook, you can work with several types of data at the same time, including mailboxes, contacts and calendars. You may notice that each of these tools opens a separate Outlook window. If you do not want this to happen, you can configure Outlook so that it only opens a single window when it launches.
Close all of the Outlook windows that are currently open by clicking on the red "X" symbol in the upper-right corner of each. Do not use the "Exit" command in the "File" menu.
Open the "Start" menu and click on the "Run" icon.
Type "outlook.exe /recycle" into the dialog box that appears.
Press the "OK" button.
Wait for the Microsoft Outlook application to reload. When it launches, only a single Outlook window will open.
Things You'll Need
PC running Windows XP or later
Microsoft Outlook 2003 or later