将C＃Web应用程序连接到SQL Server时出错

Question

I'm working on a newly set up laptop. There are two web projects I usually work with. One is fine. The one giving me trouble is a C# Web forms application (ASP.NET 4.5, EF 6.0).

The following is the error I get when trying to connect to the database via the application -

Exception:

The underlying provider failed on Open.

Inner Exception:

A network-related or instance-specific error occurred while establishing a connection to SQL Server. The server was not found or was not accessible. Verify that the instance name is correct and that SQL Server is configured to allow remote connections. (provider: TCP Provider, error: 0 - No connection could be made because the target machine actively refused it.)

Debugging using IIS Express and ASP.NET Development Server give me the same result. My connection string is also good - it's more or less the same as the one in the other project I use, bar their actual names. For clarity here it is:

<connectionStrings>
  <clear/>
  <add name="RetailerEntities" connectionString="Data Source=localhost;Network Library=DBMSSOCN;Initial Catalog=db;user id=sa;password=password;MultipleActiveResultSets=true;"/>
  <add name="RetailerCContext" connectionString="metadata=res://*/Providers.Model.csdl|res://*/Providers.Model.ssdl|res://*/Providers.Model.msl;provider=System.Data.SqlClient;provider connection string=&quot;Data Source=localhost;Network Library=DBMSSOCN;Initial Catalog=db;user id=sa;password=password;MultipleActiveResultSets=true;&quot;" providerName="System.Data.EntityClient" />
</connectionStrings>

I should also mention, both projects I work with access the same database, so it is strange that one would connect and one wouldn't.

Funnily enough, there are no issues with this project once it's deployed into a production environment, so it looks to just be a local issue on my laptop. This makes me wonder is it some sort of permissions issue.

The stack trace is:

   at System.Data.Entity.Core.EntityClient.EntityConnection.Open()
   at System.Data.Entity.Core.Objects.ObjectContext.EnsureConnection()
   at System.Data.Entity.Core.Objects.ObjectContext.ExecuteInTransaction[T](Func`1 func, IDbExecutionStrategy executionStrategy, Boolean startLocalTransaction, Boolean releaseConnectionOnSuccess)
   at System.Data.Entity.Core.Objects.ObjectQuery`1.<>c__DisplayClassb.<GetResults>b__9()
   at System.Data.Entity.SqlServer.DefaultSqlExecutionStrategy.Execute[TResult](Func`1 operation)
   at System.Data.Entity.Core.Objects.ObjectQuery`1.GetResults(Nullable`1 forMergeOption)
   at System.Data.Entity.Core.Objects.ObjectQuery`1.<System.Collections.Generic.IEnumerable<T>.GetEnumerator>b__0()
   at System.Lazy`1.CreateValue()
   at System.Lazy`1.LazyInitValue()
   at System.Lazy`1.get_Value()
   at System.Data.Entity.Internal.LazyEnumerator`1.MoveNext()
   at System.Collections.Generic.List`1..ctor(IEnumerable`1 collection)
   at System.Linq.Enumerable.ToList[TSource](IEnumerable`1 source)
   at Retailer.Library.DB.ConfigurationController.GetConfigurations() in c:\Development\Retail\RetailerC.Library\DB\ConfigurationController.cs:line 41
   at RetailerC.Web.Default.BindDdlSearchUrl() in c:\Development\Retail\RetailerC.Web\Default.aspx.cs:line 449
   at RetailerC.Web.Default.Page_Load(Object sender, EventArgs e) in c:\Development\Retail\RetailerC.Web\Default.aspx.cs:line 79

If anyone had any ideas, or has experienced anything similar, I'd be grateful to hear.

Answer 1

I removed 'Network Library=DBMSSOCN;' from the connection strings and it seems to be working fine now. Not sure why, but it's done it for me..