Oracle Solution for Error ora-01245

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

What triggered the Error:

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.

What should we do to fix it:

Either bring the file online and recover it, or take it offline with the FOR DROP option.