unable to open file <str> for snapshot area <str>

  Explanation:   The  storage  area  file  corresponding  to   the
  snapshot area could not be opened successfully.

  User Action:  Check the error message to make sure the  filename
  is  correct.   If  the  filename  is  not  correct, the FILID is
  corrupt.  In this case, restore the  database,  and  verify  the
  database root again.