Recipient’s email address is resolved incorrectly to a contact’s email address in an Exchange Server 2010 environment

Consider the following scenario:

• You have a user (use A) whose email address contains a hyphen (-) in a Microsoft Exchange Server 2010 environment.
• You create a contact that contains a hyphen. The email address of the contact resembles the email address of user A.
• You create an email message by using Outlook Web App.
• You type the email address of user A in the To, Cc, or Bcc box.
• You click the Check Names button.

In this scenario, the email address that you typed is resolved incorrectly to the email address of the contact. Therefore, you send the email message to the wrong recipient unintentionally.

For example, user A’s email address is y-abc@example.com. The contact’s email address is m-abc@example.com. You type y-abc@example.com in Outlook Web App. Then, you click the Check Names button. In this situation, the email address is resolved incorrectly to m-abc@example.com instead of y-abc@example.com.