Entity произошла ошибка базового поставщика в open

senzacionalesenzacionale

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I had this error and found a few solutions:

Looking at your connection string, it looks valid. I found this blog post, the problem here is that they were using Integrated Security. If you are running on IIS, your IIS user needs access to the database.

If you are using Entity Framework with Transactions, Entity Framework automatically opens and closes a connection with each database call. So when using transactions, you are attempting to spread a transaction out over multiple connections. This elevates to MSDTC.

(See this reference for more information.)

Changing my code to the following fixed it:

using (DatabaseEntities context = new DatabaseEntities())
{
    context.Connection.Open();
    // the rest
}

context.Connection.Open() didn’t help solving my problem so I tried enabling «Allow Remote Clients» in DTC config, no more error.

In windows 7 you can open the DTC config by running dcomcnfg, Component Services -> Computers -> My Computer -> Distributed Transaction Coordinator -> Right click to Local DTC -> Security.

MajidMajid

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I found the problem was that I had the server path within the connection string in one of these variants:

SERVERSQLEXPRESS
SERVER

When really I should have:

.SQLEXPRESS

For some reason I got the error whenever it had difficulty locating the instance of SQL.

answered Jul 21, 2011 at 10:19

This is common issue only. Even I have faced this issue. On the development machine, configured with Windows authentication, it is worked perfectly:

<add name="ShoppingCartAdminEntities" connectionString="metadata=res://*/ShoppingCartAPIModel.csdl|res://*/ShoppingCartAPIModel.ssdl|res://*/ShoppingCartAPIModel.msl;provider=System.Data.SqlClient;provider connection string=&quot;data source=.SQlExpress;initial catalog=ShoppingCartAdmin;Integrated Security=True;multipleactiveresultsets=True;application name=EntityFramework&quot;" providerName="System.Data.EntityClient" />

Once hosted in IIS with the same configuration, I got this error:

The underlying provider failed on Open

It was solved changing connectionString in the configuration file:

<add name="MyEntities" connectionString="metadata=res://*/ShoppingCartAPIModel.csdl|res://*/ShoppingCartAPIModel.ssdl|res://*/ShoppingCartAPIModel.msl;provider=System.Data.SqlClient;provider connection string=&quot;data source=MACHINE_NameSQlExpress;initial catalog=ShoppingCartAdmin;persist security info=True;user id=sa;password=notmyrealpassword;multipleactiveresultsets=True;application name=EntityFramework&quot;" providerName="System.Data.EntityClient" />

Other common mistakes could be:

1. Database service could be stopped
2. Data Source attributes pointing to a local database with Windows authentication and hosted in IIS
3. Username and password could be wrong.

When you receive this exception, make sure to expand the detail and look at the inner exception details as it will provide details on why the login failed. In my case the connection string contained a user that did not have access to my database.

Regardless of whether you use Integrated Security (the context of the logged in Windows User) or an individual SQL account, make sure that the user has proper access under ‘Security’ for the database you are trying to access to prevent this issue.

answered Jan 3, 2013 at 16:03

This can also happen if you restore a database and the user already exists with different schema, leaving you unable to assign the correct permissions.

To correct this run:

USE your_database
EXEC sp_change_users_login 'Auto_Fix', 'user', NULL, 'cf'
GO
EXEC sp_change_users_login 'update_one', 'user', 'user'
GO

answered Nov 5, 2012 at 15:46

answered Jan 30, 2014 at 20:28

I had a similar issue with exceptions due to the connection state, then I realized I had my domain service class variable marked as static (by mistake).

My guess is that once the service library is loaded into memory, each new call ends up using the same static variable value (domain service instance), causing conflicts via the connection state.

I think also that each client call resulted in a new thread, so multiple threads accessing the same domain service instance equated to a train wreck.

I had the same problem but what worked for me was removing this from the Connection String:

persist security info=True

answered Apr 17, 2013 at 13:47

answered Sep 30, 2013 at 15:35

alexkalexk

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answered May 9, 2013 at 10:28

Tom StickelTom Stickel

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answered Apr 16, 2018 at 11:04

rikketrikket

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iberiber

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answered Aug 4, 2013 at 13:52

answered Dec 9, 2013 at 17:23

answered May 2, 2014 at 14:01

GabrielGabriel

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Jaydeep ShilJaydeep Shil

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live-lovelive-love

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I have solved this way.

Step 1:
Open Internet Information Service Manager

Step 2:
Click on Application Pools in left navigation tree.

Step 3:
Select your version Pool. In my case, I am using ASP .Net v4.0. If you dont have this version, select DefaultAppPool.

Step 4:
Right click on step 3, and select advanced settings.

Step 5:
Select Identity in properties window and click the button to change the value.

Step 6:
Select Local System in Built-in accounts combo box and click ok.
That’s it. Now run your application. Everything works well.

Codeproject Solution : the-underlying-provider-failed-on-open

answered Jul 25, 2017 at 4:59

Horev IvanHorev Ivan

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