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Why rename it? Old, corrupted chainstate folders still use a few GB.
Wouldn't it be better to delete the folder entirely?
That besides the point.
Of course OP can do that to get rid of the restricted files but it's what previously suggested and followed by the OP.
But the point is, this particular issue can't be solved by
--reindex/--reindex-chainstate alone as it somehow can't wipe the chainstate directory by itself.
This is correct, I renamed the old, locked "chainstate" folder to "chain" then ran bitcoind -reindex. Bitcoin core created a new chainstate folder, until that point, --reindex/--reindex-chainstate wouldnt work.