Step 1 ) Download and install the excellent (and free!) Paragon Backup.
Step 2 ) Do a FULL backup using Windows backup. You can store it on a 3rd hard disk, or USB drive or even another computer on your network. I used a networked computer. This is our emergency only, last resort, in case all else fails backup and will not be used if all goes well. Make the recovery disk when prompted. As a further precaution boot into the recovery disk and ensure you can access the backup. Do not skip this step!
Step 3 ) Now do a FULL backup using Paragon Backup. Same location if you like (this is the one we will restore later). Make sure you backup the MBR, System Reserved (~100MB) and windows partitions. Minimum 3 ‘partitions’. If that’s all you have then fine, just make sure you backup ALL your partitions. The MBR is not, strictly speaking, a partition but you will see it listed.
Step 4 ) Create the Paragon backup/restore CD or USB (I used a USB thumb)
Step 5 ) Boot the Paragon backup/restore disk you created in step 4, and make sure you can access the backup you created in step 3, If you used the network like me, then you will need to set it up using the ‘Configure network’ option. If you cannot access the backup then you will need to move the backup. Just make sure you can access the backup using the Paragon backup/restore disk before you continue.
Step 6 ) Reboot and enter your RAID BIOS, destroy your array, do not create a new array.
Step 7 ) boot the Paragon backup/restore, now restore your backup of windows 7 to disk 0. Make sure to restore the MBR and the ~100MB ‘System Reserved’ partitions as well as the windows partition.
Step 8 ) Once completed you should now be able to boot into windows.
Step 9 ) Open ‘Device Manager’ and look for your RAID driver. Uninstall it. You should be prompted to reboot.
Step 10 ) Enter your Mainboard BIOS setup, Change the sata controller mode from RAID to SATA (you could try AHCI but if it wont boot you will need to follow one of the many guides on enabling AHCI).
Step 11 ) If all went well your done, windows will install the correct drivers for your sata controller and want to reboot again most likely, but basically that’s it.
For full explanation and links to the various tools used please visit :-