Lync Picture in Outlook

I have a few users who experience the following:

1.  The picture for a contact in Lync is correct.  

2.  The picture for the same contact in outlook is incorrect.

3.  The picture for the incorrect contact is correct on other PC's.

Not really sure what to delete here.  I imagine there is an incorrect cache file somewhere on the user with the incorrect information's PC.  I just don;t know where and Google is not helping.  

Using Lync 2010 and Outlook 2010 on Windows 7 (64 bit edition).

Thanks in advance.

Matt 

Matt Dillon