Assume that you try to add a new file store in Microsoft Lync Server 2010, Topology Builder. When you type a Distributed File System file share paths, Topology Builder might not accept the values. For example, if you type domain.com in File Server FQDN or root\folder in File Share.
This issue occurs because Topology Builder accepts neither the share folder that contains subdirectory nor the file server FQDN that has the same domain as the Session Initiation Protocol (SIP) domain.
To resolve this issue, install the following cumulative updates:
2670334 Description of the cumulative update for Lync Server 2010, Core Components: February 2012
2670358 Description of the cumulative update for Lync Server 2010, Administrative Tools: February 2012