I downloaded DotNetNuke CMS source code from
When i am running via visual studio 2012 and SQL 2008 Express.
while running application it is showing me following error.
- renaming has done for release.config to web.config.
- SiteSqlServer values has changed to database i created still it is showing same error.
Server Error in '/DotNetNuke_Community' 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.
Line 573: //and also generates the appropriate error message if it cannot be initialised correctly
Line 575: string strMessage = DataProvider.Instance().GetProviderPath();
Line 577: //get current database version from DB
Source File: d:\DotNetNuke_Community_07.01.00_Source\Community\Library\Common\Globals.cs Line: 575