I solved the problem by deleting software required to control Ximeta NDAS.
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Network Direct Attached Storage - Wikipedia, the free encyclopedia )
I had replaced the HDD in the NDAS box and updated the software at the same time. Damn thing doesn't work now, I think it's because I have an older version of the enclosure software that is not compatible with the new external HDD (not the same drive that went to read only, that is on a USB not ethernet.)
Ah, such joy!