When you view your contacts in Microsoft Lync 2010, Microsoft Lync 2013, Microsoft Outlook 2013, or Microsoft Outlook Web App, you may experience the following issues:
There are duplicate contacts in the contact list.
The contacts contain incorrect information.
You can't remove contacts from Lync, Outlook 2013, or Outlook Web App.
Outlook 2013 slows down when it resolves contacts or opens contact cards.
To resolve this issue, follow these steps:
Install the latest Lync 2013 (15.0.4517.1005 or newer) or Lync 2010 (4.0.7577.4419 or newer) update. To do this, go to one of the following Microsoft Knowledge Base articles:
Contact Microsoft Customer Support Services to obtain a tool that will remove the duplicate contacts.
Because of an issue that is now resolved in the latest Lync 2013 update, Lync 2013 would create duplicate contacts in the Lync Contacts folder in the mailbox. The Lync Contacts folder is read-only. Therefore, these contacts cannot be removed manually from Outlook. However, we recommend that you don't remove them manually by using another method because this can delete the contact list in Lync.
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