Having the same problem here as well.  Fresh install, all default options, it returns this error when I go to the url.

Parameter count does not match Parameter Value count.

Description: An unhandled exception occurred during the execution of the current web request. Please review the stack trace for more information about the error and where it originated in the code.

Exception Details: System.ArgumentException: Parameter count does not match Parameter Value count.

Source Error:

[ArgumentException: Parameter count does not match Parameter Value count.]
   Microsoft.ApplicationBlocks.Data.SqlHelper.AssignParameterValues(SqlParameter[] commandParameters, Object[] parameterValues) +146
   Microsoft.ApplicationBlocks.Data.SqlHelper.ExecuteNonQuery(String connectionString, String spName, Object[] parameterValues) +226
   DotNetNuke.Data.SqlDataProvider.UpdatePortalAlias(String PortalAlias, Int32 lastModifiedByUserID) +126
   DotNetNuke.Entities.Portals.PortalAliasController.GetPortalAliasInfo(String PortalAlias) +685
   DotNetNuke.HttpModules.UrlRewriteModule.RewriteUrl(HttpApplication app) +3339
   DotNetNuke.HttpModules.UrlRewriteModule.OnBeginRequest(Object s, EventArgs e) +1291
   System.Web.SyncEventExecutionStep.System.Web.HttpApplication.IExecutionStep.Execute() +68
   System.Web.HttpApplication.ExecuteStep(IExecutionStep step, Boolean& completedSynchronously) +75

 I finally managed to install DNN 5.1.2. What I did is the following:

1) Installed DNN 5.1.2, as I used to, but ended up in the error situation like the previous posts in this thread
2) Removed all tables, stored procedures, views and functions from the database manually
3) Entered the URL http://www.mysite.nl/www/install/install.aspx

Then a installation script starts and installs all perfectly. I don't know why the initial,  regular, appraoch did not work. But I'm glad it is working now.

Kind regards,
Berthold

I THINK I FOUND THE PROBLEM FOR ME!:

In my case the problem was the following:

I have a Database for the DNN calles "DNNCustomerName" and have a Database with all my datas needed in the Webportal called "CustomerName1".
I have a local  instance of the Portal in DNN Version 4.9.5 and a live Portal in Version 5.2.3.
I wanted to have all new datas in my local DNN instance. So I copied the "DNNCustomerName" into my local instance and changed the wb.config-entry to the new Database. Now I think the Problem is that I can not have the Portal in Version 4.9.5 and the DNN-Database in Version 5.2.3. 

possible way to fix this:

- Upgrade the local instance of your DNN to Version 5.2.3  

- Use the old Database and copy the needed(known) datas into the existing old DNNCustomerName.

Hope I could help a bit.

greetings Marc