The connection string for the database 'Test' does not exist or does not have a valid provider.

Feb 24, 2014 at 11:53 PM
I have a very wired issue hosting a service on IIS.

I created a library TestLibrary and tested the functionality and than deployed on IIS.

Now when I try to access it, it shows below message

The connection string for the database 'Test' does not exist or does not have a valid provider.

and my connection string is correct and it has the provider too and I am able to test it with I run through IIS Express.
<add name="TestConnection" connectionString="Data Source=SERVER;Initial Catalog=DatabaseNAME;User ID=UID;Password=PWD" providerName="System.Data.SqlClient" />
Also could this be related to Entity Lib 6?

Can anyone please help?
Feb 24, 2014 at 11:55 PM
Edited Feb 24, 2014 at 11:56 PM
Also could there is something related to this. This is OLD connection string from the application which I am moving to Ent lib

Provider=SQLOLEDB;Data Source=.;database=EFS;uid=sa;pwd=nsaini;

Feb 26, 2014 at 7:35 AM
Based on the posted message it looks like the code is requesting a database with a connection string called "Test" but the connection string in the configuration file is called "TestConnection".

Randy Levy
Enterprise Library support engineer
Support How-to
Aug 14, 2014 at 7:38 AM
Edited Aug 14, 2014 at 7:41 AM
I get the exact same message by my configurations are a little more complicated: I'm using EF5 with Oracle managed data access provider. I think the configuration of the Oracle managed provider is messing up the EntLib. Here are the relevant parts of my config file:

 <section name="dataConfiguration" type="Microsoft.Practices.EnterpriseLibrary.Data.Configuration.DatabaseSettings, Microsoft.Practices.EnterpriseLibrary.Data, Version=, Culture=neutral, PublicKeyToken=31bf3856ad364e35" requirePermission="true" />
    <section name="entityFramework" type="System.Data.Entity.Internal.ConfigFile.EntityFrameworkSection, EntityFramework, Version=, Culture=neutral, PublicKeyToken=b77a5c561934e089" requirePermission="false" />
<loggingConfiguration name="" tracingEnabled="true" defaultCategory="General">
      <add name="Database Trace Listener" type="Microsoft.Practices.EnterpriseLibrary.Logging.Database.FormattedDatabaseTraceListener, Microsoft.Practices.EnterpriseLibrary.Logging.Database, Version=, Culture=neutral, PublicKeyToken=31bf3856ad364e35" 
listenerDataType="Microsoft.Practices.EnterpriseLibrary.Logging.Database.Configuration.FormattedDatabaseTraceListenerData, Microsoft.Practices.EnterpriseLibrary.Logging.Database, Version=, Culture=neutral, PublicKeyToken=31bf3856ad364e35"
        databaseInstanceName="CroEntities" writeLogStoredProcName="WriteLog"
        addCategoryStoredProcName="AddCategory" formatter="Text Formatter"
        traceOutputOptions="LogicalOperationStack, DateTime, Timestamp, ProcessId, ThreadId, Callstack" />
<dataConfiguration defaultDatabase="CroEntities" />
    <add name="CroEntities" connectionString="metadata=res://*/CroModel.csdl|res://*/CroModel.ssdl|res://*/CroModel.msl;provider=Oracle.ManagedDataAccess.Client;provider connection string=&quot;DATA SOURCE=oracle;PASSWORD=pwd;PERSIST SECURITY INFO=True;USER ID=usr&quot;"
      providerName="System.Data.EntityClient" />
    <defaultConnectionFactory type="System.Data.Entity.Infrastructure.SqlConnectionFactory, EntityFramework" />
    <version number="">
        <dataSource alias="oracle" descriptor="(DESCRIPTION = (ADDRESS_LIST = (ADDRESS = (PROTOCOL = TCP)(HOST = = 1521)))(CONNECT_DATA =(SERVICE_NAME =" />
The DB configuration works fine with EF5 and I have no problems to connect to the Oracle DB. However when I run the following code:
DatabaseFactory.SetDatabaseProviderFactory(new DatabaseProviderFactory());
LogWriterFactory logWriterFactory = new LogWriterFactory();
LogWriter defaultWriter = logWriterFactory.Create();
The code fails on the last line with "The connection string for the database 'CroEntities' does not exist or does not have a valid provider."
Any ideas how I might be able to solve this?

Thank you,
Aug 14, 2014 at 8:04 AM
The Data Access Application Block is a wrapper over ADO.NET so I don't think it's going to work with a provider of type System.Data.EntityClient. Also, I don't think there is a EntLib database implementation for the Oracle.ManagedDataAccess.Client provider. The built-in OracleDatabase is deprecated and uses System.Data.OracleClient while the EntLibContrib OralceDatabase uses the Oracle.DataAccess.Client provider. See this work item from EntLibContrib: Managed ODP.NET Support (Oracle.ManagedDataAccess).

Randy Levy
Enterprise Library support engineer
Support How-to
Aug 14, 2014 at 8:29 AM
Hi Randy and thank you for your quick response.
Seems like my best option is to switch to the event viewer listener until this issue is resolved
Thank you,

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