What's wrong with my links?

What's wrong with my links?

I have a really strange issue since a few days. Every time I copy a link from a comment (Youtube, forums, 9gag etc) and paste it in the browser bar I get a 404 error from the site where the page should be.

Here's an example from wikipedia:

Error

404 – File not found

http://en.wikipedia.org/%E2%80%8Bwiki/So%E2%80%A6

We could not find the above page on our servers.

Did you mean to type http://en.wikipedia.org/wiki/%E2%80%8Bwi%E2%80%A6 You will be automatically redirected there in five seconds.

Alternatively, you can visit the Main Page or read more information about this type of error.

A project of the Wikimedia Foundation

I filled in: http://en.wikipedia.org/%E2%80%8Bwiki/Sombrero_G%E...

Which is a completely valid link. When I type the link myself (letter by letter) everything is fine. I can also normally follow hyperlinks, but when it's just plain text that I have to copy-paste it doesn't work...

I even pasted the text in word, retyped it exactly and then pasted that in the adress bar and it suddenly worked.

How is that possible?

I also can't make hyperlinks myself. When I use that "href" code or so it won't turn into a hyperlink but keep on showing the complete text (in black) with the code and all.

The strange thing is that in this question my hyperlinks work fine, I just can't do it when commenting somewhere.