The Volatile User Cache option allows for volatile user information that has previously been cached on a workstation to remain on the workstation for a specified period. Therefore, volatile users are not created or removed at every login or logout. This promotes faster logins for volatile users because NWGINA does not need to spend cycles recreating the user desktop.
The cache makes it possible for a user to continue using the workstation even when the workstation is disconnected from the network and the user is not a registered user on the workstation.
If you make the user a member of the group Guest, the Volatile User Cache option is not supported.