This article explains how to clear the AutoComplete Cache in Outlook Web App. This is commonly done when a misspelled email address or a cached email address returns a non delivery response (bounce back) when the email address appears to be correct.

Delete an entry from the list using OWA

1.  Log into your mailbox via Outlook Web App at

2.  Create a new email or meeting request

3.  Begin typing the entry you want to delete until you see it in the Auto Complete list

4.  To remove one entry from the list, highlight the name in the Auto Complete list, arrow up and arrow down allow you to highlight the name you want to remove

5.  When the entry is highlighted, press the Delete button on your keyboard.

Delete the entire list using OWA Light

1.  Log into mailbox using Outlook Web App Light at

2.  Go to Options > Messaging

3.  Under Email Name Resolution, click "Clear Most Recent Recipients List"