This error can be caused by two things;
1) You have tried to download the file from the email link more than once. To correct, login to your account on ClickWrestle and click the Purchased Videos link. This will allow you to download the file.
2) You are using a download accelerator or download manager program. These programs cause issue with the ClickWrestle downloads and must be disabled.
If you have followed the above steps and are still having problems, please contact us at http://www.clickwrestle.com/content/contact-us