This issue was more noticable in the Lync 2010 client because it showed the origin of the contact in Lync.
You can use the Migration dashboard in the Exchange Administration Center (EAC) to display migration status information for all users in a migration batch.
A user can tell if the address book is completely downloaded when the “Address book synchronizing” status goes away when searching for a contact – as shown here: As been previously well documented, if you need to force the Lync client to download the address book immediately you can.
The name of the migration batch and the following commands are displayed at the top of the window.
The following table describes each field displayed in the details pane.
Identifies the specific point in the migration process for each mail object in the migration batch.
) for a specific mailbox, mail contact, or distribution group, click the mailbox, contact, or distribution group in the list.
Status information for the selected mail object is displayed in the details pane.
Here is a sample screen shot of the associated bad Outlook contact used in the example above: In this case the domain name in the Email and IM address fields were different than the SIP address for this contact in the Lync address book.