Help! Problems Installing DNN 4.5.5

[Wissam]

Hello,

I am installing (not upgrading) DotNetNuke version 4.5.5 on my computer

I followed everything stated in this article http://www.mitchelsellers.com/Blogs/tabid/54/articleType/ArticleView/articleId/119/Installing-DotNetNuke-455-Locally.aspx

But now I have an error that I don't know how to handle, and it's kinda annoying me so I need a little help here.

What should I do to manage it?

Note that I followed every single step in the article, and my connection string is the following "server=localhost\\SQLEXPRESS;Trusted_connection=tr ue;database=*****;"



Server Error in '/DotNetNuke455' Application.
Instance failure.
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.InvalidOperationException: Instance failure.

Source Error:

Line 80:
Line 81: 'Determine the Upgrade status and redirect to Install.aspx
Line 82: Select Case GetUpgradeStatus()
Line 83: Case Globals.UpgradeStatus.Install
Line 84: If AutoUpgrade Then


Source File: c:\inetpub\wwwroot\DotNetNuke455\App_Code\Global.a sax.vb Line: 82

Stack Trace:

[InvalidOperationException: Instance failure.]
System.Data.ProviderBase.DbConnectionPool.GetConne ction(DbConnection owningObject) +437
System.Data.ProviderBase.DbConnectionFactory.GetCo nnection(DbConnection owningConnection) +82
System.Data.ProviderBase.DbConnectionClosed.OpenCo nnection(DbConnection outerConnection, DbConnectionFactory connectionFactory) +105
System.Data.SqlClient.SqlConnection.Open() +111
DotNetNuke.Data.SqlDataProvider.ExecuteADOScript(S tring SQL) +69
DotNetNuke.Data.SqlDataProvider.ExecuteScript(Stri ng Script, Boolean UseTransactions) +780
DotNetNuke.Data.SqlDataProvider.ExecuteScript(Stri ng Script) +6
DotNetNuke.Data.SqlDataProvider.GetProviderPath() +191
DotNetNuke.Common.Globals.GetUpgradeStatus() +78
DotNetNuke.Common.Global.CheckVersion() in c:\inetpub\wwwroot\DotNetNuke455\App_Code\Global.a sax.vb:82
DotNetNuke.Common.Global.Application_Start(Object Sender, EventArgs E) in c:\inetpub\wwwroot\DotNetNuke455\App_Code\Global.a sax.vb:313


Version Information: Microsoft .NET Framework Version:2.0.50727.42; ASP.NET Version:2.0.50727.42

[Buzz]

But now I have an error that I don't know how to handle


We can't guess what the error is.

[Wissam]

We can't guess what the error is.

I did include the error message I received! (including the stack trace)
It's in the code section