I had a free "wordpress .com" website for a long time and I was using it with the domain name that I bought from GoDaddy by using domain mapping for a long time. I decided to buy a wordpress hosting from GoDaddy and transfer all my database here. But the problem is I can't get rid of domain mapping. Whenever I tried to reach the WP Admin, I got the message of: "Warning! Domain mapping upgrade for this domain not found. Please log in and go to the Domains Upgrades page of your blog to use this domain. "
What can I do to stop this domain mapping and use this domain name with my new WordPress hosting?
Did you check that your DNS records reflect the new nameservers for your new hosting account? Now that you are leaving WordPress.com that link you provided isn't relevant -- that indicates that possibly we haven't move the domain back to GoDaddy by designating correct names servers yet.
You also want to make sure that there are no straggling DNS A or CNAME records from your previous host.