ORA-19694: some changed blocks were not found in the change tracking file

RMAN-00571: ===========================================================
RMAN-00569: =============== ERROR MESSAGE STACK FOLLOWS ===============
RMAN-00571: ===========================================================
RMAN-03009: failure of backup command on ORA_DISK_1 channel at 05/28/2013 0


Disable block change tracking:

SQL> select * from v$block_change_tracking;

STATUS
----------
FILENAME
--------------------------------------------------------------------------------
     BYTES
----------
ENABLED
/u01/oradata/PPC/block_change_tracking.f
  11599872


SQL> alter database disable block change tracking;

Database altered.

SQL> select * from v$block_change_tracking;

STATUS
----------
FILENAME
--------------------------------------------------------------------------------
     BYTES
----------
DISABLED