Do you have a backup of that datafile and all the archivelogs from that backup to the point the datafile was removed?

I think you get these errors when the controlfile has been recreated and a file left out - Oracle KNOWS about the datafile as its in the dictionary so puts a "MISSING" entry in its place.

Read up on
"Note:77338.1
Subject: Datafiles named 'MISSING' " in Metalink.

If you still have the datafile on backup, put it back in place and try recreating the controlfile again. You will also need all the archived redo logs from the point the datafile left the database.

If you DONT have the datafile on backup but all the archived redologs you can probably recreate the datafile with 'alter database create datafile ' and recover - applying all thre redo.

If you DONT have the datafile and dont have all the redo then either go back to your last complete backup containing the file, or you may have to drop the tablespace - depends entirely on whether the database is live/test etc and how much data will be lost, the importance of the data etc.

-B