LS220DE only Boots into EM mode

[MtnGoatXJ]

When this unit was new the start up with two 1TB WD reds was flawless. Ran for almost a year until I attempted to up grade to 3TB drives. Once these drives were installed the unit will only boot into EM mode. I have two solid red hd lights. The upper light will flash white then go solid white. NAV finds the NAS in EM mode. I shutdown then restart. While the upper light is flashing red I depress and hold the reset button momentarily. The lower light flashes bright white then goes out as the upper light flashes white until it goes solid. Again the unit is found in EM mode.

WTH? Been going through every forum and google search I can find without getting this drive back on line.

What am I doing wrong?

[Eastmarch]

So, the operating system is found on the original drives. You can't just yank the old drives out and put new ones in.

There isn't a supported way to do what you are talking about, but you can put a 3TB in a mirror set with an original drive. Once rebuilt, you can remove the original and create a new mirror across the other 3TB.