Here are three possible problems and resolutions for each. A. DA56NT drivers are not properly registered. To resolve, close DAServer, Find NT56.REG in C:\Maestro, C:\maestro\Templates or C:\Maestro\utils. Open with Regini.exe in c:\Maestro or c:\Maestro\utils. Restart Computer. To confirm they are registered and running, go to computer management (right click My Computer then choose Manage). Open Device Manager, then on Top Menu under View, select show Hidden Devices. This will give you a new section of Non Plug and play listings and the DA Set should be listed there. If you have two DA Cards both DA56NT and DA56NT1 should be listed and started. B. When upgrading to Windows 2000, it's possible you created a new partition for the OS, which would change the path to the drivers. The NT56.Reg file (located in C:\Maestro\utils or in C:\Maestro) looks like this: \registry\machine\system\currentcontrolset\services\DA56NT Start = REG_DWORD 0x00000002 ErrorControl = REG_DWORD 0x00000001 Group = Base Type = REG_DWORD 0x00000001 ImagePath = \Device\Harddisk0\Partition1\winnt\system32\drivers\da56nt.sys Parameters Device0 BusNumber = REG_DWORD 0x00000000 Configuration Error = REG_DWORD 0xffffffff Firmware = \Device\Harddisk0\Partition1\winnt\system32\drivers\a56bios.lod InterfaceType = REG_DWORD 0x00000001 Interrupt = REG_DWORD 0x0000000a PortAddress = REG_DWORD 0x00000320 Devices WaveOut0 = REG_DWORD 0x00000002 So, if the OS was now on Partition2, you would need to edit the reg file and change the Image Path and Firmware Lines. (See Registering NT56.Reg under (A) C. There is a conflicting device. The DA565NT sets are hard coded for IRQ since they are ISA boards. DA56NT is Interrupt 10, DA56NT1 is Int 11. Make sure you have reserved those interrupts in BIOS for Legacy ISA so that the PCI bus doesn't try to grab them.