Something strange happened to my website, please help

Selected answers from the Dumb SEO Questions Facebook & G+ community.

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  W.E. Jonk: The web site that is on your profile does serve wildcard sub domains. That is your server responds a HTTP 200 on every (random) sub domain and serves your main web site. This is not best practice [1] (although it can be useful in very specific cases). In general it is best practice to serve only one version of your web site.
  
  Furthermore you use (mostly not all) relative URL's instead of absolute, which means that once Googlebot or any other user visits the sub-domain they could navigate on the sub domain and they aren't send to the main site (similar for images) [2]. Although it doesn't really matter to have absolute URL's, it does help to avoid mistakes. Therefore the consensus is to use absolute URL's if you can.
  
  You don't use rel canonical. Rel canonical can be a HTTP header (handy for files like pdf's) or a link element in the head section of a web page. In short, rel canonical tells search engines which URL is preferred, which URL they should crawl and serve in the search results [3]. I looked at your site and you do serve the canonical version in <meta property="og:url" content="">. So I guess it should be rather easy to implement. Although it is not necessarily to serve rel canonical on the canonical version it does help social media buttons like the plus one [4].
  
  [1] ;https://plus.google.com/+PierreFar/posts/4K2sG3QjGpm
  [2] ;http://yoast.com/relative-urls-issues/
  [3] ;https://support.google.com/webmasters/answer/139394?hl=en
  [4] ;https://developers.google.com/+/web/+1button/#target-url
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  Stefan Ivanov: Thank you, I ;thought that when i use 301 redirect there would be no problems with the urls. Thanks for the ;recommendation gonna fix the urls now and put rel canonical.
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  W.E. Jonk: I don't know what else is on the server or which sub domains do have unique web sites but the main problem is the (mis) configuration of the server to allow wildcard sub-domains. ;
  
  The rel canonical and the absolute URL comments are more of a safeguard to make sure that if something doesn't go as planned the rel canonical kicks in. But that doesn't really solve the main problem, which is wildcard sub domains.
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  Stefan Ivanov: Hmm i think i found where is the problem, Im using WAMP and i got some virtual hosts enabled that point to same port and url.. Thank you again, going to fix them tommorow:)
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  W.E. Jonk: Re-thinking/reading it sounds like this configuration went on for quite a long time. Therefore it might be that a number of links are pointing to a wildcard sub-domain. If that is the case then I would 301 them to the appropriate page (unless it doesn't make sense like ritalin.example.com or some other weird looking URL). Furthermore you did mention that G has i47.example.com in their index. That particular sub domain should be 301'ed to the root domain.  ;
  
  Imo I would first investigate which wild card sub domains get traffic ect before shutting them down....
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  Stefan Ivanov: Actually none of them brings traffic. I`ve done many mistakes while creating the page and there were a lot of problems (Dublicate content and titles spammy links from seo check sites) and mistakes that i `ve done in the code. I`ve 301 redirected that sub domain.. Now waiting again for more problems :) Thank you again for the fast responce and help:)
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  W.E. Jonk: From the expert panel in this weeks SEO Questions hangout on air on 02:29:30 into the YouTube video: https://dumbseoquestions.com/q/something_strange_happened_to_my_website_please_help