We have tried the PORTALPATH variable in the RPD, but that's also not working as expected. Is there any other settings to be done other than configuring the variable in RPD to get it work.

Additional information on this topic:  The problem seems to exist with several things that are related to individual users and their preferences.  Three others that I have found are: (1) The user's Favorites are lost after signing out; (2) The Home screen loses its "most recent 9 things" in the "Others" section after signing out; (3) The list of the 6 most recent objects touched are missing under the Open option.