Microsoft StreamInsight: “The type or namespace name ComplexEventProcessing does not exist in the namespace Microsoft”


error streaminsight complex event processing version 21In this blog post, I’ll document how I solved the error “The type or namespace name ComplexEventProcessing does not exist in the namespace Microsoft”. Here are the steps:

1. I browsed through other errors/warnings as well – I was also missing assemblies from Reactive Extensions and so I added them first.

2. For my scenario, I had installed StreamInsight 2.0 successfully on my machine but I downloaded the sample that needed assemblies from StreamInsight 2.1 – notice the version mismatch here? That was the problem!

3. One of the message said “Could not locate assembly Microsoft.ComplexEventProcessing version =” – notice the version = – it suggested that I needed the assemblies from StreamInsight 2.1

4. So I downloaded “Microsoft® SQL Server® StreamInsight 2.1” and installed it. And it worked!

5. FYI: I found the Microsoft.ComplexEventProcessing assembly on my machine at C:WindowsMicrosoft.NETassemblyGAC_MSILMicrosoft.ComplexEventProcessing*

That’s about it for this post. I hope it helps someone who is having issues with finding the assembly with the right version number to get started working with StreamInsight.

How I installed StreamInsight 2.0 on my demo machine:


I installed StreamInsight 2.0 on my demo machine today and so I thought I would document the process.

Before we begin, few references to existing documents on the interwebs: Official documentation about Installation is here: and Introduction to concepts of StreamInsight can be accessed via the following resources:

1)      MSDN documentation:

2)      Pluralsight:

3)      SQL server central article:

4)      A channel 9 video pointed out by Johan Ahlen:

Now, here are the steps that I took to install StreamInsight on my demo machine:

1)      I located the StreamInsight installer inside the SQL Server 2012 Developer edition setup that I had:

1 Installing streaminsight sql server developer edition

Note that even though StreamInsight is licensed with SQL Server – It is different “software” that solves different technical problem(s). And note that StreamInsight does not have dependencies on SQL Server. It is a separate install.

2. On the Instance Configuration page, I added “StreamInsightInstaller” as the instance name. This is the first instance of StreamInsight that I am installing on my demo machine

3. On next dialog box, I added the product key that I have for SQL Server Developer edition. You also have the option to activate 180 day trial.

4. Then specify the StreamInsight service and group settings

5. Click on Install on next dialog box

6. You would also need to install the SQL compact edition. To do that, I navigated to C:Program FilesMicrosoft StreamInsight 2.0Redist

Note that, if you have chosen the x64 version then you would have to first install the x86 version of SQL Server compact and then the x64 version of SQL Server Compact.2 stream insight install sql serve compact edition

7. Now installation is complete at this point.

8. If the StreamInsight Service is not started, then go to services and start it.

3 install streaminsight service not started

In services: Right click > Start:

4 windows service streaminsight start

9. Now, You can run samples. To access them you can go to Start > all programs > StreamInsight Samples

5. stream insight samples installation


In this blog-post, we saw how to install StreamInsight 2.0 on your machine.