SAS Discovery Error - Cannot Reboot

Hi all, I have a Dell Precision T7500 which was working fine and then with no changes in configuration failed to reboot properly. During the BIOS section of the reboot I get the following error SAS Discovery Error 0X00000002 on Adapter0, Port 1 Then Windows Server 2012 R2 begins to boot BUT before getting to the Logon Screen I get a black screen with a cursor on it. The cursor responds to the mouse but otherwise I can not elicit any response from the machine (Ctl Alt Del and Alt Tab etc do nothing). If I restart the machine and press Ctl C at the appropriate time to view more information on the SAS Discovery Error I get the following screen: LSI Corp Config Utility for Dell SAS v6.22.03.00 (2008.08.06) Adapter List Global Properties Adapter PCI PCI PCI FW Revision Status Boot Bus Dev Fnc Order SAS6IR 05 00 00 0.25.47.00-IR ERROR 0 I am stuck at the moment and really need to get this machine working again. Any help would be appreciated. Terry Clancy