I had an interesting experience with Google recently, related to Electronic Journal of Probability (EJP) and Electronic Communications in Probability (ECP). As a managing editor of EJP and ECP, I check from time to time how EJP and ECP do appear in Google Search. Bizarrely, more than one year ago, the URLs http://ejp.ejpecp.org/ and http://ecp.ejpecp.org/, which are the main URLs of the journals, have completely lost their rank in Google searches. The first result given by the Google search engine for the search “Electronic Journal of Probability” was the mirror site http://www.emis.ams.org/journals/EJP-ECP, while the main URL http://ejp.ejpecp.org/ was not present in the first pages of results. A scandal! The problem seemed specific to the Google search engine, and Microsoft Bing for instance was not affected.
It took me more than a year to solve this ranking problem. My first attempt was to contact some people that I know in San Francisco to obtain a contact at Google. This approach gave nothing. Google is huge. My second attempt consisted in using Google Webmaster Tools, a service provided by Google to fine tune the interaction between a website and the Google search engine. This approach gave me some interesting information on the websites but no clue on the source of the initial problem.
Finally, after few months of various attempts, I decided to explain my problem in the Webmaster Central Help Forum of the Google Product Forums. Several contributors provided very quickly various tentative explanations, leading at the end to the solution of the problem. In fact, the domain ejpecp.org was considered by Google as being parked! That is why its rank was so low! The reason was first the presence of an HTTP 302 temporary redirection (instead of an HTTP 301 permanent redirection) of the URL http://www.ejpecp.org/ to http://journals.ejpecp.org/, and second the presence of advertisement front-pages on non-used sub-domains such as www.ejp.ejpecp.org set by the DNS provider (which is NetworkSolutions as one can check in the whois database). The solution was then easy to implement: modify the HTTP redirection and the DNS tables. It works now!