George's IOCell NAS lost connection after he upgraded to Windows 10. Leo says that what's important with a RAID NAS is having it built into the firmware. If the operating system itself is doing the reading with drivers, it's possible that the NAS company hasn't a driver for Windows 10. As such, Windows can't see it. If it was a network connection, then it would have to appear as a standard, mountable drive for Windows to see it on the network. It's just a matter of mounting it. It'll need to support modern SMB, though. If it has an older SMB protocol, then Windows 10 won't see it anyway.
If it mounts and doesn't see the RAID, well that's another problem. Windows may see them as drives, but not as a RAID. So you'd need a driver to read them. And that points to a proprietary issue. George says the company is out of business. It's possible that there's an open-source driver out there. But what you could do is downgrade back to Windows 7, or use another Windows 7 computer, copy the data off the NAS, and then retire it. You should anyway since there's no support for it anymore.