I recently ran into this issue during a vulnerability assessment performed at work, so I figured I would add it here so that maybe it will help someone else out.
Server Message Blocks Protocol (SMB) is the file sharing protocol used by default on Windows-based computers. SMB 1.0 was designed for early Windows network operating systems such as Microsoft LAN Manager and Windows for Workgroups, but until Windows Server 2008 and Vista, all Microsoft-based operating systems continued to use it more or less in its original format.
SMB 2.0 was introduced in Windows Vista and Windows Server 2008. SMB 2.0 is designed for the needs of the next generation of file servers. Windows Server 2008 and Windows Vista support both SMB 1.0 and SMB 2.0 in order to preserve backward compatibility.