I recently migrated an Umbraco 5 site from a live environment to my local environment to make some changes, and ran into an issue. I backed up the database of the live site and restored it locally, updated the connection string located in the Hive config file to point to my local database (located at ~App_DataUmbracoHiveConfigweb.config), and the site still would not load. I was presented with the following screen:
Install Umbraco 5.0.0 RTM
Welcome to Umbraco 5
It looks like Umbraco isn't installed yet - click here to launch the install wizard.
Umbraco 5.0.0 RTM runs on ASP.NET MVC3. This is a standard MVC-powered page included as a demo of how your MVC application can serve pages alongside those managed by Umbraco CMS.
To learn more about ASP.NET MVC visit http://asp.net/mvc
After a few minutes of troubleshooting, I discovered that the issue was simply that the production environment was using a different user account for Umbraco to access the database than I was using locally, and even though I changed the connection string to reflect this, I forgot to associate the username with the database after the restore:
After checking the appropriate database roles for my user account everything was working again. Since Umbraco 5 doesn't error or give any warning about why it is at the install screen, this wasted a little bit of my time. Hopefully this helps one of you troubleshoot a similar issue.