For mass storage devices only, remote access is also available through client drive mapping, where the drives on the user device are automatically mapped to drive letters on the virtual desktop when users log on. The drives are displayed as shared folders with mapped drive letters. To configure client drive mapping, use the Client removable drives setting in the File Redirection Policy Settings section of the ICA Policy Settings.
The main differences between the two types of remoting policy are:
If both client drive mapping and the USB rule are enabled, then if a mass storage device is inserted before a session starts, it will be redirected using client drive mapping first, before being considered for redirection through USB support. If it is inserted after a session has started, it will be considered for redirection using USB support before client drive mapping. Automatic support of devices upon insertion, however, depends on the client being used and the individual user preferences; for further information, see the relevant client documentation.