Joe, I brought this up today also with the Apple tech.
He pointed that going into the finder is a no no. I'm been using the finder to grab files from TM, (maybe 5-6 times ) over the last few years. He says doing this and not using the TM interface is 100x worse than not ejecting a drive properly. I never knew this.
Hence TM is not working, it goes back in time ok, it finds the missing files ok, but then nothing happens with I click replace or keep both.
I'm running a disk repair (his suggestion), on the TM 8 TB external, 4 hours now and progress bar is not even at any level yet! So it may be toast. If so, he recommends putting that hardrive in the closet, buying a new one and starting fresh if that does not fix it..
BTW Joe, any progress on servers.. seems like getting worse, these posts timing out...
