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I just downloaded a trial and start the C# sample app. It started fine, but nothing really happened so I clicked around a bit. After a short period and while I was doing something else (I started browsing the installed file for the crm sample data to create) the sample app crashed.

Here is the stacktrace:
A first chance exception of type 'System.InvalidOperationException' occurred in Devart.Data.Oracle.dll
System.Transactions Critical: 0 : http://msdn.microsoft.com/TraceCodes/Sy ... dUnhandled exceptionLinqDemo.vshost.exeSystem.NullReferenceException, mscorlib, Version=2.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089Object reference not set to an instance of an object. at Devart.Common.DbConnectionPoolGroup.a(DbConnectionPool A_0)
at Devart.Common.DbConnectionPoolGroup.a(Object A_0)
at System.Threading._TimerCallback.TimerCallback_Context(Object state)
at System.Threading.ExecutionContext.Run(ExecutionContext executionContext, ContextCallback callback, Object state)
at System.Threading._TimerCallback.PerformTimerCallback(Object state)System.NullReferenceException: Object reference not set to an instance of an object.
at Devart.Common.DbConnectionPoolGroup.a(DbConnectionPool A_0)
at Devart.Common.DbConnectionPoolGroup.a(Object A_0)
at System.Threading._TimerCallback.TimerCallback_Context(Object state)
at System.Threading.ExecutionContext.Run(ExecutionContext executionContext, ContextCallback callback, Object state)
at System.Threading._TimerCallback.PerformTimerCallback(Object state)

Such a rapid crash doesn't really create a high level of trust in your component, so I'm writing to you to see if there is a simple explanation of why this happened. I did not create any specific databases for the sample app, did not configure any connection strings or anything similarly so it may be entirely my fault. I'll just like to know what exactly went wrong so I go start from there...

Best regards
Soren

There was a problem with working with invalid connections in the latest build. The issue is already fixed, and the fix will be available in the nearest build.

To work around the problem, please ensure that you change the connection string(s) used in the sample so that it points to a server available in your environment.

Thanks for the info, the exceptions that were thrown also seemed a bit random when I tried different connectionstrings.

Just a quick question that is a bit off topic, but I'll ask it anyway. I can't seem to get a connectionstring to connect to a Oracle XE installation running locally on my machine? I've tried using your sample app and I even wrote some code that used your IDbConnection adapter to try to hook it up, but it is not working. I'm a total Oracle newbie so I am hope you can spare a few helpful tricks to connecting with your product?

Nevermind, I'm was being stupid and figured out my own error.

We've released the new 3.0.14 build of LinqConnect that includes the fix for the null-reference exception. The new build can be downloaded from
http://www.devart.com/linqconnect/download.html
(the trial and free versions only) or from Registered Users' Area (for users with active subscription).

As for the connection string, please specify whether you are connecting in the OCI or Direct mode.

In the first case, you should create an entry in the tnsnames.ora file of your Oracle client:
http://www.orafaq.com/wiki/Tnsnames.ora
For the details on configuring the Direct mode, please refer to the corresponding article.

If the problem persists, please specify the approximate connection string you are using.