THE DOCUMENT DISK IS FULL OR THE FILE IS
READ-ONLY.
 
■ Erase files you do not need. Then choose File
  Save again.
■ Save the file to another formatted disk with
  more space available.
■ If the file is read-only, save it with a
  different name or to a different disk or
  directory.
■ Use the DOS ATTRIB command (or OS/2 equivalent)
  to change the read-only attribute of the file.