topic Restart QVS service: "System.NullReferenceException: Object reference not set to an instance of an object" in QlikView

Restart QVS service: "System.NullReferenceException: Object reference not set to an instance of an object"

Mon, 26 Jan 2026 18:19:17 GMT

Hi all,

I've had a look around and the closest post I can find is this one (which doesn't help much unfortunately):

http://community.qlik.com/forums/t/33070.aspx

Due to resource limitations and user behaviour/expectations we've set up a Windows scheduled task to restart the service every morning. It's a very simple batch file which issues a NET STOP, waits for 5 mins then issues a NET START. When this happens the following event is logged to the Applicaiton Log:

Event Type: Error
Event Source: CommandCenterService
Event Category: None
Event ID: 0
Date: 13/09/2010
Time: 07:02:38
User: N/A
Description:
System.NullReferenceException: Object reference not set to an instance of an object.
at QlikView.Backstage.Wrappers.QvsWrapper.CallFunction(String methodname, String iStartElement, String iStartAttribute, IXmlSerializable arguments, IXmlSerializable outpar)
at QlikView.Backstage.Wrappers.QvsWrapper.GetServerStatus()
at QVPublisherCommandCenterService.ServiceImpl.DoGetServiceStatuses()

This is occurring on all our QlikView Server 9.0 SR5 servers including our test server which is a very modest Windows Server 2003 R2 SP2 server with 2 cores and 8Gb RAM. Activity on this server is minimal at present.

Does anyone know why this error is occuring and/or how to fix it?

Cheers,

Martin

Restart QVS service: "System.NullReferenceException: Object reference not set to an instance of an object"

Thu, 16 Sep 2010 11:09:44 GMT

Hi,
at the time you restart the service, you was executing some document distribution or reloading?
Command center service, monitor the QlikView Server service for understand if it's alive, stop command center first than QVS, strange behaviour anyway, hope help, regards.

Restart QVS service: "System.NullReferenceException: Object reference not set to an instance of an object"

Thu, 16 Sep 2010 15:42:33 GMT

Nope, the last document to be reloaded/distributed finished hours before the restart took place.

That does make sense though, about the Command Center service monitoring the QlikView Server service. And I agree, it seems odd behaviour to throw a System.NullReferenceException rather than trapping the event and logging it appropriately.