Every time I connect my external WD Thunderbolt drive (8TB RAID 1 mirrored) to my MacBook Pro (early 2013) I get a warning pop up saying the drive in slot b is missing.
I cannot be 100% but it feels to me that this has been happening since upgrading to Mac OS Sierra.
The drive is functioning fine with all the data there and accessible. If I open WD Drive Utilities and run the diagnosis tests everything passes successfully.
If the drive is on its way out how do I know when the tools say its fine?
If the drive is fine how do I get rid of the annoying (and thus incorrect) message?