Did you try clearing the sockets?
Clearing RAID Controller Sockets
The RAID controller stores the model number and a serial number of the disks in what is called sockets. This information is used to detect when a disk has been changed. When a RAID controller is shipped, this socket information is clear. There are times this information must be cleared, for example, when you want to install a hard disk that already has a different version of software or configuration, or if you start up the system with one drive installed and that drive is defective.
To clear the sockets, perform the following steps.
1. While power is OFF, verify both hard disks are removed.
2. Turn the MXe power on. Wait until the fault LEDs on the RAID controller are orange.
3. Turn the MXe power off. The RAID controller sockets are now clear.
4. Proceed with the installation/upgrade.