By default, when searching the Offline Address Book, Outlook resolves e-mail addresses using Ambiguous Name Resolution. With Ambiguous Name Resolution, Outlook suggests additional possible matches (if they exist) even if there is a name that matches exactly the e-mail alias entered. By enabling this setting, you can change the behavior so that Outlook returns a single e-mail address if it exactly matches an e-mail alias.
| Registry Hive | HKEY_CURRENT_USER |
| Registry Path | software\policies\microsoft\exchange\exchange provider |
| Value Name | oab exact alias match |
| Value Type | REG_DWORD |
| Enabled Value | 1 |
| Disabled Value | 0 |