ORA-01245: offline file string will be lost if RESETLOGS is done

admin

ORA-01245: offline file string will be lost if RESETLOGS is done
Cause: Attempting to do an OPEN RESETLOGS with a file that will be lost
because it is offline. The file was not taken offline with the FOR DROP option.
Action: Either bring the file online and recover it, or take it offline with the FOR
DROP option.