We have a subdomain "sub.domain.com" which is the old version of our site. The current version is at "domain.com". Though, there are no links to sub.domain.com from anywhere on the web, Google was able to find it and has spidered and indexed the site almost completely.
We were able to retain the URL structure, so sub.domain.com/test.htm and www.domain.com/test.htm will essentially have similar or same content.
To fix this: 1. I did a 301 redirect of all urls from sub.domain.com to www.domain.com 2. I added sub.domain.com in Google Webmasters to try the "Change of address" option. But it seems the option is available only for root domains.
1. I was hit by the 3% optimization that google did recently and I wonder it is because of this. Did Google consider this as a link spam, since both sub and www have same content.
2. Is there anything that I can do apart from 301 redirects to fix the problem? I cannot remove the subdomain since the URLs already exist on Google and will be 404 errors, which is more worse
How can I get rid of all sub.domain.com entries from the Google index?