RMAN restoration failed with error RMAN-06026

Hi there,

I am trying to restore database in different server by RMAN backup. But every time I got error and it failed : 

RMAN-06026: some targets not found - aborting restore

RMAN-06100: no channel to restore a backup or copy of datafile 283

RMAN-06100: no channel to restore a backup or copy of datafile 282

RMAN-06100: no channel to restore a backup or copy of datafile 281

RMAN-06100: no channel to restore a backup or copy of datafile 280

.......
....

SQL> show parameter recov

NAME                                 TYPE        VALUE

------------------------------------ ----------- ------------------------------

db_recovery_file_dest                string

db_recovery_file_dest_size           big integer 0

db_unrecoverable_scn_tracking        boolean     TRUE