OCI-19602
cannot backup or copy active file in NOARCHIVELOG mode
Cause
An attempt was made to copy or backup a file that was not closed cleanly, and the database was in NOARCHIVELOG mode. This is not allowed because, when restored, the file requires redo application before it is usable, and redo is not currently being saved beyond the contents of the online redo logs.
Action
Take the tablespace cleanly offline or close the database and retry the copy or backup.