I have a v4.6.1 website running on MySQL v5.1.34, on a live web server.

I copied the website to my PC (Windows 7) and used Navicat to copy the database also to my PC - when I try to access the admin I get -

Server Error in '/' Application.


            
 Object reference not set to an instance of an object. 

            

             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.NullReferenceException: Object reference not set to an instance of an object.



            Source Error: 



            

               

                  

                      

An unhandled exception was generated during the execution of the current
 web request. Information regarding the origin and location of the 
exception can be identified using the exception stack trace below.

                  
               
            


            


            Stack Trace: 



            

               

                  

                      
[NullReferenceException: Object reference not set to an instance of an object.]
   umbraco.presentation.install.steps.Definitions.DefaultUser.Completed() +13
   umbraco.cms.businesslogic.installer.InstallerStepCollection.GotoNextStep(String key) +184
   umbraco.presentation.install._default.GotoNextStep(String currentStep) +26
   umbraco.presentation.install.Helper.RedirectToNextStep(Page page) +56
   umbraco.presentation.install.steps.license.gotoNextStep(Object sender, EventArgs e) +17
   System.Web.UI.WebControls.LinkButton.OnClick(EventArgs e) +118
   System.Web.UI.WebControls.LinkButton.RaisePostBackEvent(String eventArgument) +113
   System.Web.UI.WebControls.LinkButton.System.Web.UI.IPostBackEventHandler.RaisePostBackEvent(String eventArgument) +9
   System.Web.UI.Page.RaisePostBackEvent(IPostBackEventHandler sourceControl, String eventArgument) +13
   System.Web.UI.Page.RaisePostBackEvent(NameValueCollection postData) +176
   System.Web.UI.Page.ProcessRequestMain(Boolean includeStagesBeforeAsyncPoint, Boolean includeStagesAfterAsyncPoint) +5563







            


            



            Version Information: Microsoft .NET Framework Version:4.0.30319; ASP.NET Version:4.0.30319.1

            

If I trash the copied database and run through the install routine, it works fine.

Any ideas on how I get the local site to work with a copy of the "live" MySQL database? I have tried scripting the database from "live" and running the script locally but that doesn't work either :-(