I am very new to Oracle, and trying to restore a oracle 8i database on win 2000 server.

• I have one week old database backup (backup taken with exp command), and i want to restore it now.
• Now I am unable to login through sqlplus (got shutdown in progress error)
• I have a backup and i want to restore it, but oracle is not starting at all, and 'imp' command is failing.

I started sqlplus / as sysdba and following is the log of what i am trying to do. Can some one guide me further.

SQL> shutdown immediate;
ORA-01109: database not open    

Database dismounted.
ORACLE instance shut down.
SQL> startup;
ORACLE instance started.

Total System Global Area  143423516 bytes
Fixed Size                    75804 bytes
Variable Size              58105856 bytes
Database Buffers           85164032 bytes
Redo Buffers                  77824 bytes
Database mounted.
ORA-01589: must use RESETLOGS or NORESETLOGS option for database open


SQL> shutdown immediate;
ORA-01109: database not open


Database dismounted.
ORACLE instance shut down.
SQL> startup mount;
ORACLE instance started.

Total System Global Area  143423516 bytes
Fixed Size                    75804 bytes
Variable Size              58105856 bytes
Database Buffers           85164032 bytes
Redo Buffers                  77824 bytes
Database mounted.
SQL> alter database open;
alter database open
*
ERROR at line 1:
ORA-01589: must use RESETLOGS or NORESETLOGS option for database open


SQL> alter database open resetlogs;
alter database open resetlogs
*
ERROR at line 1:
ORA-01245: offline file 1 will be lost if RESETLOGS is done
ORA-01110: data file 1: 'C:\ORACLE\ORADATA\ABCD\SYSTEM01.DBF'