Why this page?

I've had several problems with the tConfig and all the Mods I've downloaded:

I can't play any world, only create it.The only thing it says me is:

"Item.Web.Extensions, Version=, Culture=neutral,PublicKeyToken=31bf3856ad364e35' ni una de sus dependencias. El s..."

I've tried anything, even re-installing tConfig.

Please, guys, I need help!