First of all, don't forget to ask your sysadmin to setup autodiscover, as it will make the process of setting up Thunderbird much easier.
Below, step by step according to Outlook version used, which you can usually check when opening Outlook or in the Help menu/About. There's also a web site with generic Outlook setup which can be useful, so you can view screen shots.
Also notice that if this is the first time you open Outlook since its install, a window will immediately pop up asking you to setup your email account. Click yes and proceed and follow our instructions starting with section in which you start typing in your account data.
Outlook 2013/2010:
- Click on the File menu and it shall show you the Info tab
- Click on + Add Account
- Type in your full name, e-mail address and password and click on Next
- Click on Allow when asked about autodiscover.xml
- Click on Finish
Outlook 2007:
Go to Tools -> Account Settings and click on New
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