Merge pull request #95966 from VMrenato/patch-16

Update concept-azure-ad-connect-sync-default-configuration.md

Author: Jak-MS

articles/active-directory/hybrid/concept-azure-ad-connect-sync-default-configuration.md

@@ -71,6 +71,7 @@ The following attribute rules apply:
 ### Contact out-of-box rules
 A contact object must satisfy the following to be synchronized:
 
+* Must have mail attribute value.
 * The contact must be mail-enabled. It is verified with the following rules:
   * `IsPresent([proxyAddresses]) = True)`. The proxyAddresses attribute must be populated.
   * A primary email address can be found in either the proxyAddresses attribute or the mail attribute. The presence of an \@ is used to verify that the content is an email address. One of these two rules must be evaluated to True.