Problem in opening the DB

Hi Friends,
I need yr help very urgently.
I did the recovery
After recoevry when i start the DB, getting the error:

can u please help me
please see below for the error


regards,
praveen

SQL> startup
ORACLE instance started.

Total System Global Area 5186227160 bytes
Fixed Size 744408 bytes
Variable Size 989855744 bytes
Database Buffers 4194304000 bytes
Redo Buffers 1323008 bytes
Database mounted.
ORA-01187: cannot read from file 1 because it failed verification tests
ORA-01110: data file 1: '/oa_ebs_t662d/oradata03/t662data/system01.dbf'

Try to select checkpoint_change from v$datafile_header to see if they are the same. Oracle's error message means
01187, 00000, "cannot read from file %s because it failed verification tests"
// *Cause: The data file did not pass the checks to insure it is part of the
// database. Reads are not allowed until it is verified.
// *Action: Make the correct file available to the database. Then, either open
// the database, or execute ALTER SYSTEM CHECK DATAFILES.