Last week I was at a client site upgrading their 2007 environment to 2010 environment. I went the Database attach route. I got all the servers running and the upgrade went through without any issues. I asked them to point the DNS entry to the appropriate server and they should be up and running. I was WRONG.
As soon as they pointed their DNS entry to this new server. Some of the subsites started showing the wrong lists. The contacts list was showing some document library and some lists started giving errors that it does not even have the list. I was totally confused with this and after remoting in I started comparing and found out that the server url address would work but the actual DNS entry would not work. Thats when I started thinking about the Alternate Access Mappings.
So, I looked into Alternate Access Mappings and WALLA. There it was. The URL was still pointing to the server address instead of the Intranet URL. Changed the URL and it started working perfectly. Got all my lists back and everything was working as it was supposed to work.
Got one client happy. Few more to go 🙂