The ClientAccess property is used to determine all of the
access permissions that are currently granted to an authenticated
client session and optionally change those permissions. For a list of
user access rights that can be granted to the client, see
User Access Constants.
When modifying the value of this property, it is recommended that
you use bitwise OR and AND operands to set and clear specific bitflags.
The exception is when using the ftpAccessDefault permission.
If you wish to reset the client session to use the default permissions
based on the server configuration and client authentication, then you
should assign this value directly to the ClientAccess property.
This property should only be accessed within an event handler such
as OnCommand because its value is specific to the client
session that raised the event. This property will always return a
value of zero outside of an event handler, and an exception will be
raised if you attempt to modify this property outside of an event