Outlook is a great email client and it has a lot of features. However, sometimes it can be difficult to find the right email address when you want to send an email. This is because Outlook stores the addresses in the Auto-Complete Email Address Cache. This cache can help you quickly find the right email address when you need to send an email. To clear the Auto-Complete Email Address Cache in Outlook, follow these steps:

  1. Open Outlook and click on the Tools button.
  2. Click on the Options button.
  3. Click on the Clear Auto-Complete Email Address Cache button.
  4. In Outlook, click on the messages tab and then click on the Send button.

The problem comes in when you put in a bad address, and then every time you go to type in the email address, the incorrect one appears in the auto complete list.

To fix this problem, there are two ways around this. The easiest way is this:

Start typing in the address that shows up incorrectly. Hit the Down arrow key to select the auto completed address. Hit the Delete key to delete the auto complete address

The other way is by opening the profile folder and deleting the .nk2 file.

Open up windows explorer, and paste the following into the address bar: %APPDATA%\Microsoft\Outlook Delete the Outlook. NK2 file that you find in this folder.