Not sure whether this forums is suitable for my topic. Pls move in suitable forums if posted in wrong.
About 2 years back I have started a blog - e.g. url - blog.name.com . I thought meanwhile I update the blog and later develop my site name.com . But due to lack of time from personal and job life I could not get time to develop a design for my site. So after a year I changed my mind and thought the blog content should be sifted in main domain like name.com . It's going fine. Google indexing the new changed stuffs. But I am finding problem in search results. For one of my targeted Keywords it shows in page 4 but the url shows the old one i.e. blog.name.com . Also the same url is showing as index page too.
If you are using WordPress there is a plugin that redirects your old URL link to your new one automatically. I used it on one site and it worked, but before I implemented it I waited too long and I lost a lot of backlinks. If you do it quickly your site wont suffer but if you are like I am and wait a long time it could suffer some.
The plugin is called Permalinks Migration. But like I said it needs to be done quickly to get the full benefit. It sounds like it might help some, but you may have allowed too much time to pass for all of the links to be switched out, unless you had a redirect for the old pages.
I'm using Simple 301 Redirects plugin on Wordpress and it's working just fine. If you still have access to the old blog and if it's on Wordpress, give it a try. As someone suggested above, you can also login to your Google Webmaster account and notify Google about the domain change.
Apart from doing a request in google webmaster for domain change, you should disallow bots to crawl blog directory. Specify the below line in robots.txt file and upload it in the root directory. User-Agent: * Disallow: /blog/
Now you can do a URL removal request in google webmaster tools to remove the entire directory from the search result. Make sure to do a 301 redirect of blog subdomain main domain.