Requiem super_secret file is "corrupt" and won't install

[Mr. Poopybuthole]

After finding all 9 artifacts and getting the password at the end I clicked on super_secret in the game's files, typed in the password and made it to the install page.

However it said "CRC failed in the encrypted file super_secret.exe (wrong password?)"
I haven't a clue what that meant so I clicked install anyway to see what would happen and it said installation files are corrupt and to download a fresh copy and try again.

So I deleted and reinstalled the game's local files, tried it again and got the same issue.

How can I get a working super_secret file?

[Lautrec]

If you're on Steam, Have you tried to verify the integrity of the game cache? If not, go to your library and right-click on Penumbra Requiem -> Go to Properties -> Select Local Files -> Verify integrity of game cache