The google link looks ok, so the problem must be on your site - your index file might have been tampered with. The divert appears to swing into action only if the inbound request is coming via a search engine, easily detected. (I tried it on bing and yahoo with same result). All 3 links go to forbidden(dot)4pu(dot)com - obviously a spam site or something similar.
I would guess that your site has been hacked and your index file has been tampered with, so you’ll need to change all your access details immediately, and then you’ll have to start the clean up. If you’re not responsible for managing the site, then speak to whoever is.
There’s probably a lot more I could say here, but it’s a start.
Good point about the old version of WP. I didn’t realise you were using WP. Once you have your site cleaned up, you might try installing the Wordfence plugin (search for it in the ‘add new’ plugins control panel) - it has some nice features and among many other things, it generates warning emails when plugins or WP need updating.
Thanks everyone, I was hoping not having to reinstall Wordpress but looks like that may be my only option I’ve changed much of the code to remove code which I noticed was not suppose to be in there but still no luck.