I just purchased Syberia 1 but when I download it and tried to install the game I got a message saying that the files are corrupt. What can I do about this?

If the files are corrupt you'll have to download them again.

How did you downloaded your files ? If you used the downloader you can try downloading them using your browser instead or if used your browser to download them give the downloader a try.

Also make sure it isn't your Anti Virus and/or Firewall getting in the way of the download.

Disable your antivirus and try redownloading. Should fix the problem.