Error connecting SQL Azure - Network access for Distributed Transaction Manager (MSDTC) has been disabled

Question

Sometimes I have an error connecting SQL Azure. The error occurs in an asp.net application and in a windows service running on VM in Azure. Error details:
System.Data.Entity.Core.EntityException: The underlying provider failed on Open. ---> System.Transactions.TransactionManagerCommunicationException: Network access for Distributed Transaction Manager (MSDTC) has been disabled. Please enable DTC for network
access in the security configuration for MSDTC using the Component Services Administrative tool. ---> System.Runtime.InteropServices.COMException: The transaction manager has disabled its support for remote/network transactions. (Exception from HRESULT:
0x8004D024)
   at System.Transactions.Oletx.IDtcProxyShimFactory.ReceiveTransaction(UInt32 propgationTokenSize, Byte[] propgationToken, IntPtr managedIdentifier, Guid& transactionIdentifier, OletxTransactionIsolationLevel& isolationLevel,
ITransactionShim& transactionShim)
   at System.Transactions.TransactionInterop.GetOletxTransactionFromTransmitterPropigationToken(Byte[] propagationToken)
   --- End of inner exception stack trace ---
   at System.Transactions.Oletx.OletxTransactionManager.ProxyException(COMException comException)
   at System.Transactions.TransactionInterop.GetOletxTransactionFromTransmitterPropigationToken(Byte[] propagationToken)
   at System.Transactions.TransactionStatePSPEOperation.PSPEPromote(InternalTransaction tx)
   at System.Transactions.TransactionStateDelegatedBase.EnterState(InternalTransaction tx)
   at System.Transactions.EnlistableStates.Promote(InternalTransaction tx)
   at System.Transactions.Transaction.Promote()
   at System.Transactions.TransactionInterop.ConvertToOletxTransaction(Transaction transaction)
   at System.Transactions.TransactionInterop.GetExportCookie(Transaction transaction, Byte[] whereabouts)
   at System.Data.SqlClient.SqlInternalConnection.EnlistNonNull(Transaction tx)
   at System.Data.ProviderBase.DbConnectionPool.PrepareConnection(DbConnection owningObject, DbConnectionInternal obj, Transaction transaction)
   at System.Data.ProviderBase.DbConnectionPool.TryGetConnection(DbConnection owningObject, UInt32 waitForMultipleObjectsTimeout, Boolean allowCreate, Boolean onlyOneCheckConnection, DbConnectionOptions userOptions, DbConnectionInternal&
connection)
   at System.Data.ProviderBase.DbConnectionPool.TryGetConnection(DbConnection owningObject, TaskCompletionSource`1 retry, DbConnectionOptions userOptions, DbConnectionInternal& connection)
   at System.Data.ProviderBase.DbConnectionFactory.TryGetConnection(DbConnection owningConnection, TaskCompletionSource`1 retry, DbConnectionOptions userOptions, DbConnectionInternal oldConnection, DbConnectionInternal& connection)
   at System.Data.ProviderBase.DbConnectionInternal.TryOpenConnectionInternal(DbConnection outerConnection, DbConnectionFactory connectionFactory, TaskCompletionSource`1 retry, DbConnectionOptions userOptions)
   at System.Data.SqlClient.SqlConnection.TryOpenInner(TaskCompletionSource`1 retry)
   at System.Data.SqlClient.SqlConnection.TryOpen(TaskCompletionSource`1 retry)
   at System.Data.SqlClient.SqlConnection.Open()
   at System.Data.Entity.SqlServer.DefaultSqlExecutionStrategy.<>c__DisplayClass1.<Execute>b__0()
   at System.Data.Entity.SqlServer.DefaultSqlExecutionStrategy.Execute[TResult](Func`1 operation)
   at System.Data.Entity.Core.EntityClient.EntityConnection.Open()
   --- End of inner exception stack trace ---
   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.DataClasses.EntityReference`1.Load(MergeOption mergeOption)
   at System.Data.Entity.Core.Objects.DataClasses.RelatedEnd.DeferredLoad()
   at System.Data.Entity.Core.Objects.Internal.LazyLoadBehavior.LoadProperty[TItem](TItem propertyValue, String relationshipName, String targetRoleName, Boolean mustBeNull, Object wrapperObject)
   at System.Data.Entity.Core.Objects.Internal.LazyLoadBehavior.<>c__DisplayClass7`2.<GetInterceptorDelegate>b__2(TProxy proxy, TItem item)

Answer 1

Hello,
I am not an expert in MSDTC but as we know,SQL Azure Database does not support
distributed transactions. This means that SQL Azure doesn’t allow Microsoft Distributed Transaction Coordinator (MS DTC) to delegate distributed transaction handling.
One common cause of MSDTC getting involved in Entity Framework applications is the fact that we close and reopen the same connection as needed (i.e. for each query that is executed).To avoid the stack from opening and closing the connection multiple times,
you can simply open the connection explicitly and run the queries in the same connectio.
The following thread is about a similar issue, please refer to:
http://answers.flyppdevportal.com/categories/azure/sqlazure.aspx?ID=d705a8cf-cba4-494c-96f6-96a136bd29e3
What's more, you can also try the workaround that involves setting the Enlist option of the SQL Azure connection to false. For the detail explanation, please refer to:Entity
FrameWork and SQL Azure
Regards,
Fanny Liu
Fanny Liu
TechNet Community Support