We are using Outlook and Exchange 2010.  Some of my Outlook contacts are missing the mobile # that was manually entered in and present a few months ago.  One thing that has changed is that since installing Lync 2013 client it has inserted multiple contact entries for the same person and seems to have overwritten the one's that were manually created originally in Outlook.  The Lync client does not have users mobile numbers for its contacts.

Anyone experience this issue?  Is there a fix on this?

Hi, first of all, would you please figure out which address list you are using on Outlook? Offline Address Book or GAL? One possible reason is your contacts have been updated when OAB synced with GAL.

The Lync contacts may be stored on Lync Server and we can't modify them. To determine if the Lync contacts overwrote your contacts, please figure out where your Lync contacts are stored, and also, you may post the question to the Lync forum:

http://social.technet.microsoft.com/Forums/lync/en-US/home?category=ocs

Regards.