Deus.ex.human.revolution.complete.edition.part2... Page

Right-click it and select Mount (on Windows 10/11) to treat it like a virtual disc. Run setup.exe from the new drive that appears.

This usually means part2 (or whichever part is cited) did not download completely. Delete that specific part and download it again. Deus.Ex.Human.Revolution.Complete.Edition.part2...

Multi-part archives are like a jigsaw puzzle; you need every single piece in the same folder for the extraction to work. Right-click it and select Mount (on Windows 10/11)