ORA-01211: Oracle7 data file is not from migration to Oracle8

admin

ORA-01211: Oracle7 data file is not from migration to Oracle8
Cause: The file is not a copy of the file LAST used under Oracle7. This datafile is
either a backup taken from before the migration, or the database was opened by
Oracle7 after the migration utility was run. When converting a database from
Oracle7 to Oracle8, the migration program MUST be the LAST utility to access the
database under Oracle7. Only the datafiles that were current when the migration
was done may be accessed by Oracle8.
Action: Have operating system make correct data file available to database, or
repeat the Oracle7 to Oracle8 migration. Make sure that database is NOT opened
after migration utility is run.