SQL> grant dba,sysdba,sysoper to sysman;
grant dba,sysdba,sysoper to sysman
ERROR at line 1:
ORA-01996: GRANT failed: password file
'D:\Oracle\Oracle8i\DATABASE\PWDrman.ORA' is full
When you create Password file with orapwd utility, you specify entries=n which means the maximum number of entries it can take. Once it is full, there is no way you can grant additional sysdba/ sysoper roles.
You have to delete and recreate password file. This time be sure to have enough entries specified so that it can accomodate future anticipated growth. Deleting and recreating password file is risky.