Yeah. That error message is not very clear. When I see it I always think the same thing, then I see down below where it says that it couldn't connect to the database. Here's what gets me everytime with the dnn4.x installer. By default, the web.config file is set up for SqlExpress. Since I use full-blown Sql Server, this needs to be fixed before DNN can connect to the database.

Notice in the Connection Strings part of the original "release.config" that the comment for "Connection String for SQL Server 2000/2005" is not closed until after the tag.

  <connectionStrings>
  <.. snip ..>
    <!-- Connection String for SQL Server 2000/2005
    <add
      name="SiteSqlServer"
      connectionString="Server=(local);Database=DotNetNuke;uid=;pwd=;"
      providerName="System.Data.SqlClient" />
   -->
  </connectionStrings>

Fix that and then comment out the SQL Express one. Like this...

  <connectionStrings>

    <!-- Connection String for SQL Server 2005 Express
    <add
      name="SiteSqlServer"
      connectionString="Data Source=.\SQLExpress;Integrated Security=True;User Instance=True;AttachDBFilename=|DataDirectory|Database.mdf;"
      providerName="System.Data.SqlClient" />
    -->

    <!-- Connection String for SQL Server 2000/2005 -->
    <add
      name="SiteSqlServer"
      connectionString="Server=(local);Database=dbName;Trusted_connection=yes;"
      providerName="System.Data.SqlClient" />
  </connectionStrings>

Then notice that I have changed the "uid=;pwd=;" part to "Trusted_connection=yes". If you have control over your server, you can add the ASP.NET worker process user as the database owner, and authentication is automatic. On Windows XP Pro and Windows Server 2000, the worker process is the machine's ASPNET account. On Windows Server 2003, it is the "NETWORK SERVICE" account. It is the same account that needs read write access to your site directories.


One more thing. In DNN4.x, there is another spot where you should enter the connection string for backward compatibility with older modules. Just under the <connectionStrings> area, at the beginning of the <appSettings> section, there are two connections strings. The SQL Express one is active and the SQL Server one is commented out.

  <appSettings>
    <!-- Connection String for SQL Server 2005 Express - kept for backwards compatability - legacy modules   -->
    <add key="SiteSqlServer" value="Data Source=.\SQLExpress;Integrated Security=True;User Instance=True;AttachDBFilename=|DataDirectory|Database.mdf;"/>
    <!-- Connection String for SQL Server 2000/2005 - kept for backwards compatability - legacy modules
    <add key="SiteSqlServer" value="Server=(local);Database=DotNetNuke;uid=;pwd=;"/>
    -->

Fix them like this...

  <appSettings>
    <!-- Connection String for SQL Server 2005 Express - kept for backwards compatability - legacy modules  
    <add key="SiteSqlServer" value="Data Source=.\SQLExpress;Integrated Security=True;User Instance=True;AttachDBFilename=|DataDirectory|Database.mdf;"/>
  -->
    <!-- Connection String for SQL Server 2000/2005 - kept for backwards compatability - legacy modules -->
    <add key="SiteSqlServer" value="Server=(local);Database=dbName;Trusted_connection=yes;"/>

That should do it.

You obviously have full control over your machine, so here are the steps I use to install DNN. Starting from scratch...

1. Unzip the DotNetNuke 4.02 Install zip into the directory where it will reside on the server. In my case that is D:\iis\WebSites\domain.com\webroot.

2. Right click on the WebRoot directory and select "Sharing and Security" and click the Security tab.

3. Click the "Add" button and in the "Enter the Object Names to Select" area, type "NETWORK SERVICE" without the quotes, but complete with the spaces.

4. Click the [Check Names] button and the user's name will be verified and qualified. Click OK.

5. Select the new NETWORK SERVICE user and give him "Modify" permission. He doesn't need "Full Control". Click OK.

6. Back in the WebRoot directory, Make a copy of the release.config file and rename it "web.config". Also copy the \config\SiteUrls.config file to WebRoot.

7. Open the web.config file and comment out the two SQL Express SiteSqlServer keys, and uncomment the SQL Server 2000 / 2005 ones.

8. Fix the value of them both as follows...

"Server=(local);Database=DatabaseName;trusted_connection=yes;"

Of course, if your SQL Server isn't on the same machine as IIS, then modify that part accordingly. Your database doesn't have to be called "DotNetNuke". I use the site's domain name without the tld.

Make both SiteSqlServer keys have the same connection string. Save and close the text editor.

9. Start up SQL Server Enterprise Manager and expand the "Security" section. Make sure "NETWORK SERVICE" has been added to the list of "Logins" and given default access to "master".

10. Collapse the security node, right click on the "Databases" node and select "New Database". Name the database whatever you did in the connection string and accept all defaults.

11. Expand the new database node and select "Users". Right click in the users area and select "New Database User". From the drop down list, select the "NETWORK SERVICE" account you just created. Give him dbowner access and click OK.

Close the SQL Server Enterprise Manager.

12. Open IIS manager and add a new website. Make sure you select Run Scripts (Such as ASP), because by default, that is not selected. - crazy.

I can't think of anything else.. oh! Open up the new website entry in IIS and click "Properties". Select the "ASP.NET" tab and make sure you are running the 2.x version of ASP.NET.

Now, when you open up a browser and navigate to the site, Dnn should install and run. Let me know exactly what goes wrong, or if you don't understand any of those steps.

--
Phillip

Thanks to this post I was able to get it working.  The problem had to do with the use of the NETWORK SERVICE account instead of the ASPNET account.  If you are using WindowsXP be sure to use the ASPNET account.  The "Check Names" feature can't resolve it unless you type out the whole name as "aspnet"; "asp" will not resolve.

 http://www.dotnetnuke.com/Community/ForumsDotNetNuke/tabid/795/forumid/107/threadid/17974/scope/posts/Default.aspx