Sorry guys, the answer is only partially correct.
Backup may happen happily IF you've got the backup folder in the C: drive.
Which I haven't as I move the entire structure to separate drives.
In which case you get exactly the answer I have ticked as correct:
.Net SqlClient Data Provider: Msg 3201, Level 16, State 1, Line 1
Cannot open backup device 'C:\Program Files\Microsoft SQL Server\MSSQL.1\MSSQL\Backup\DBA.bak'. Operating system error 3(error not found).
.Net SqlClient Data Provider: Msg 3013, Level 16, State 1, Line 1
BACKUP DATABASE is terminating abnormally.
How do I get my 2 points back - and my correctness rating reestablished ????????