Backup data on ML 350

[S400]

My server ML 350 g4, windows 2003 enterprice sp1, 2 hdd 72,4 gb Hot plug, raid 1 , smart array 641, 2 hdd logic(C,D).
I install windows server on C, data on D.
I ask some question :
- when windows error can't start, i want install new, how can i back up data on C and D?
(because, install by smart start will be arase data).
Thank you.

[SPa]

The issues seems that Windows has crashed and you want to reinstall while preserving your data.Options would be:

1)Repair Windows using Recovery console
2)The other option would be to manually install Windows by booting through the OS CD and provide Smart Array driver at the F6 prompt.(Windows 2003 may automatically detect as well).Do a parallel installation in another directory.

Below link gives you procedure to perform parallel installation.