This setting allows you to specify the name of an open network share allowing an NCrunch client machine to browse to workspaces on the grid node.
The network share path must correspond with a pre-configured and accessible network share on the grid node machine. NCrunch will not create network shares itself.
It's very useful to configure NCrunch grid nodes to share their workspaces so that client machines can read the workspace contents. This is because grid nodes execute tests and builds on behalf of clients, and without an open network share, there is no way for a client to browse to the files that have been built on the grid node.
The primary use of this configuration setting is realised using the 'Advanced->Browse to workspace last built for selected project' context menu option.