Apart from copying the files again after comparing the checksums what else have you done to troubleshoot the issue? Have you looked at logs, run fsck or anything?
Costasiella kuroshimae are capable of a physiological process called kleptoplasty, in which they retain the chloroplasts from the algae they feed on. Absorbing the chloroplasts from algae then enables them to indirectly perform photosynthesis.[6]
New commentary for HL2. Gonna have to play it again.