Force Lync2010 Client to update Address book

Step 1 : Update Servers

Run following command from Lync Server Management Shell

Update-CsAddressBook –Verbose

Step 2: Update Clients

Run following command from cmd ( run as an Administrator )

reg add HKLM\Software\Policies\Microsoft\Communicator /v GalDownloadInitialDelay /t REG_DWORD /d 0 /f

Exit the Lync client and delete the GalContacts.dband GalContacts.db.idxfiles from the user’s profile directory ( following location )

%userprofile%\AppData\Local\Microsoft\Communicator\sip_<username@domain>\

Log back in and Lync client will now update the address book.