Enterprise swap drives "invisible" to Mac OS

I have a G-RAID swappable unit and bought two spare 2000 Enterprise drives for backup/archive in mid 2016. I formatted them as a RAID 1, copied a modest amount of files to them and then stuck them in a desk drawer (in their antistatic sleeves). The other week I wanted to add more files to them and was dismayed when the pair came up as “degraded” in the G-Drive Utility. Fortunately one of them was readable so I backed that up on to another drive and then decided to re-format the pair as unique drives in the Disk Utility (I’ve read that RAIDs can often be more trouble than their worth). After re-formatting and copying all files the original files back to both discrete drives, I ejected them and set them aside. The next day I put them back into the RAID unit and… nothing! I mean, NOTHING. The drive Utility doesn’t even see that there’s anything there (other than the RAID unit itself).

Anyone got any thoughts? Fortunately I haven’t lost anything, but I’m assuming at this point that I’m out the $540 the two drives cost me - and I’m very reluctant to buy more G-Tech stuff even though I’ve found all the other RAID and drives I’ve bought from them to be super reliable (the other pair of Enterprise drives that came with the RAID, for instance).

thanks!

Make sure that when you are swapping the drives into the enclosure they are flush with the backplane and that when you turn the unit on each drive LED is lit up blue or else you can’t expect to get recognition.

Getting nothing at all in the configurator or recognition on the system is unlikely if attached completely because even if there are two failed drives the configurator would see the controller and that the drives were bad.

since I figured the problem is more of an OS/Disk Utility formatting issue I called Apple. while on hold for an Enterprise drive forum moderator the drives both suddenly appeared on the desktop (after a good ten minutes since last putting in the chassis!). I ran disk First Aid on them and it turned out that they needed a “boot partition” something or other. The utility “fixed” the problem on them and all is well again. pretty crazy - especially when I realized that while the OS didn’t “see” the drives, it was also completely knocking out every other drive on the Thunderbolt chain. When I would eject the (then NG) drives, then things would show up again! anyway, consider my problem “solved”…