File not open, or incompatible open mode

  Explanation: The program attempted to execute a READ statement on
  a file connector that was not opened, or not opened in the correct
  mode.

  User Action:  You must take the following actions:

      a. Verify the program logic, paying particular attention
         to the open mode.  Consult the description of the valid
         open modes for the READ statement, based on file
         organization and access mode.  Refer to the table under
         the OPEN statement in the COBOL Reference Manual for
         this information.

      b. Verify that the OPEN operation was successful.