ORA-01274----> RENAME THE UNKNOW FILE IN THE STANDBY DATABASE

RENAME THE UNKNOW FILE IN THE STANDBY DATABASE WHEN YOU PUT THE STANDBY_FILE_MANAGEMENT IN MANUAL MODE

ALERT LOG:-
File #45 added to control file as 'UNNAMED045' because
the parameter STANDBY_FILE_MANAGEMENT is set to MANUAL
The file should be manually created to continue.
Errors with log /oracle/BHUVAN/archive/10G_BHUVAN_660003944_1_257734.arc
MRP0: Background Media Recovery terminated with error 1274
Sat Sep 25 07:22:47 2010
Errors in file /oracle/BHUVAN/home/admin/BHUVAN/bdump/BHUVAN_mrp0_24491.trc:
ORA-01274: cannot add datafile '/oracle/BHUVAN/user02.dbf' - file could not be created
Some recovered datafiles maybe left media fuzzy
Media recovery may continue but open resetlogs may fail
Sat Sep 25 07:22:50 2010
Errors in file /oracle/BHUVAN/home/admin/BHUVAN/bdump/BHUVAN_mrp0_24491.trc:
ORA-01274: cannot add datafile '/oracle/BHUVAN/user02.dbf' - file could not be created
Sat Sep 25 07:22:50 2010
MRP0: Background Media Recovery process shutdown (BHUVAN)


----File #45 added to control file as 'UNNAMED045' because

select FNNAM,FNONM from x$kccfn where FNFNO=45;
/oracle/BHUVAN/home/product/10.2.0.4/dbs/UNNAMED045
/oracle/BHUVAN/user02.dbf


alter database create datafile '/oracle/BHUVAN/home/product/10.2.0.4/dbs/UNNAMED04554' as '/oracle/BHUVAN/user02.dbf';

alter database datafile 45 online;

if you are going make  standby_file_management as "AUTO in the init parameter. oracle will use the db_file_name_convert option to put the files in the respective directory in the standby database.