How to test massives amount of links? Ok, I have a wordlist of many many links (of the same site with a bit of difference in URL).

I'm certain that the majority of then will return the same result, a error page. But one will return the "correct" page.
The point is:
Is there a automatic way to test all of those links searching for the different one?
Sure, pick any coding language of you choice and iterate over the list of links connecting to the website. You will receive the website as some kind of object. If you know what the error page looks like, just check the object contains that error page (for example check for some string).

Also, just you could try one of the tools on this website:
http://www.softwaretestinghelp.com/tools/30-top-website-link-verification-testing-tools/