Step 1
On your computer, click the Start Menu and select Control Panel.
Step 2
Double-click the Mail icon. If using Windows Vista, Windows 7 or Windows 8, type Mail into the search box at the top-right of the Control Panel window to quickly find the Mail icon.
Windows Control Panel
Step 3
Click the E-mail Accounts button.
Mail Setup - outlook
Step 4
Under the E-mail tab, click the New button to add your 1&1 e-mail account. 
Account Settings Window
Step 5
Select E-mail Account and then click the Next button. 
Add Account Window
Step 6
Enter Your Name, E-mail Address, and e-mail address Password and then click the Nextbutton. 
Add Account Window
Step 7
Outlook will attempt to autodetect your e-mail settings. If a window appears attempting to configure your e-mail account using settings from the autodiscover.1and1.info website, Check the box that says Don't ask me about this website again and then click the Allow button.
Security confirmation
Step 8
After a few moments your should receive a confirmation that the e-mail account is successfully configured. Click the Finish button to complete the process. 
Add Account Window