Lync 2013 - How to refresh Lync 2013 address book - Symptom: User status showing 'unknown presence'

1. DELETE OLD ADDRESS BOOK - The location of the cached files has also changed, it is now. C:\Users\\AppData\Local\Microsoft\Office\15.0\Lync\sip_user.name@domain.com Delete GalContacts.db and GalContacts.db.idx GalContacts.db and GalContacts.db.idx are the files you are looking for to show the address book has downloaded.
2. FORCE LYNC 2013 TO UPDATE ADDRESS BOOK IMMEDIATELY - To add the key, run the following from Run/PowerShell as administrator: reg add HKLM\Software\Policies\Microsoft\Office\15.0\Lync /v GalDownloadInitialDelay /t REG_DWORD /d 0 /f 
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