< class="prominent-subhead ">

K2 5.x "Message Queuing has not been installed on this computer" error gets logged on service startup

This article was created in response to a support issue logged with K2. The content may include typographical errors and may be revised at any time without notice. This article is not considered official documentation for K2 software and is provided "as is" with no warranties.


The following error gets logged in the K2 host server log on service startup:

"Error","EventBus","7498","General","EventQueueProcessing.Main","7498 An error has occurred: System.Reflection.TargetInvocationException: Exception has been thrown by the target of an invocation. ---> System.InvalidOperationException: Message Queuing has not been installed on this computer."


This error can be easily reproduced and not necessarily specific to upgraded environments (i.e. it can also be observed with clean installations of K2 5.x). As soon as you remove MSMQ Windows components from the K2 server this error gets logged, despite the fact that in K2 5.0 - 5.2 dependency on the MSMQ component is removed. See the "Deprecated Functionality and Components" section of "Upgrading to K2 Five" document for details.

This has been logged as a bug but currently there is no fix for this. This error has no impact on K2 functionality.

Despite the fact that K2 5.0+ does not have dependencies on MSMQ it still looks for existing processes which could still use MSMQ and handles them accordingly, but this warning on service startup can be safely ignored - if there is an old process depending on MSMQ in your environment another error will be logged if it will fail due to missing MSMQ components.


This error message on service startup can be safely ignored. In K2 5.0-5.2 there is still an MSMQ mechanism built in to handle upgraded processes, and this is why this message pops up.

It is possibly to hide this error by means of editing the HostServerLogging.config and editing the following message:

<Message MsgID="7498" Severity="Error" Category="14" Name="General">
An error has occurred: {0}

You can change its Severity from Error, to Warning or Info so that it won´t be logged in the K2 host server log on default logging level.