"The operation is not valid for the state of the transaction" error and transaction scope

Question

I am getting the following error when I try to call a stored procedure that contains a SELECT Statement:

The operation is not valid for the state of the transaction

Here is the structure of my calls:

public void MyAddUpdateMethod()
{

    using (TransactionScope Scope = new TransactionScope(TransactionScopeOption.RequiresNew))
    {
        using(SQLServer Sql = new SQLServer(this.m_connstring))
        {
            //do my first add update statement

            //do my call to the select statement sp
            bool DoesRecordExist = this.SelectStatementCall(id)
        }
    }
}

public bool SelectStatementCall(System.Guid id)
{
    using(SQLServer Sql = new SQLServer(this.m_connstring)) //breaks on this line
    {
        //create parameters
        //
    }
}

Is the problem with me creating another connection to the same database within the transaction?

Answer 1

After doing some research, it seems I cannot have two connections opened to the same database with the TransactionScope block. I needed to modify my code to look like this:

public void MyAddUpdateMethod()
{
    using (TransactionScope Scope = new TransactionScope(TransactionScopeOption.RequiresNew))
    {
        using(SQLServer Sql = new SQLServer(this.m_connstring))
        {
            //do my first add update statement            
        }

        //removed the method call from the first sql server using statement
        bool DoesRecordExist = this.SelectStatementCall(id)
    }
}

public bool SelectStatementCall(System.Guid id)
{
    using(SQLServer Sql = new SQLServer(this.m_connstring))
    {
        //create parameters
    }
}

Answer 2

When I encountered this exception, there was an InnerException "Transaction Timeout". Since this was during a debug session, when I halted my code for some time inside the TransactionScope, I chose to ignore this issue.

When this specific exception with a timeout appears in deployed code, I think that the following section in you .config file will help you out:

<system.transactions> 
        <machineSettings maxTimeout="00:05:00" /> 
</system.transactions>

Answer 3

I also come across same problem, I changed transaction timeout to 15 minutes and it works. I hope this helps.

TransactionOptions options = new TransactionOptions();
options.IsolationLevel = System.Transactions.IsolationLevel.ReadCommitted;
options.Timeout = new TimeSpan(0, 15, 0);
using (TransactionScope scope = new TransactionScope(TransactionScopeOption.Required,options))
{
    sp1();
    sp2();
    ...

}

Answer 4

For any wanderer that comes across this in the future. If your application and database are on different machines and you are getting the above error especially when using TransactionScope, enable Network DTC access. Steps to do this are:

1. Add firewall rules to allow your machines to talk to each other.
2. Ensure the distributed transaction coordinator service is running
3. Enable network dtc access. Run dcomcnfg. Go to Component sevices > My Computer > Distributed Transaction Coordinator > Local DTC. Right click properties.
4. Enable network dtc access as shown.

Important: Do not edit/change the user account and password in the DTC Logon account field, leave it as is, you will end up re-installing windows if you do.

Answer 5

I've encountered this error when my Transaction is nested within another. Is it possible that the stored procedure declares its own transaction or that the calling function declares one?