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Hi All,

Applied some OS Updates Sunday Evening Using VisualCron and all of a sudden the Hyper-V Tasks for VMs that were working are all erroring.

Windows Server 2012 R2

Stop VM
Start VM

. . . also tried List VM

KB Installs were successfull . . . . List Attached via Screen print if that helps anyone

Error always the same:

Locally: "Exception in Task: System.Exception: Object reference not set to an instance of an object."

Remote is a little different <But we don't normally do this is am unsure it is related>:
Exception in Task: System.Exception: Cannot validate argument on parameter 'Session'. The argument is null or empty. Supply an argument that is not null or empty and then try the command again.

Remote was from a couple of different 7.2.0 Beta's (Including the Latest)

Anyone else had any issues ?

Have Included Powershell Equivalent Commands . . . . they remain fine if that helps.
KJDavie attached the following image(s):
Forum information
Is it a local or remote VM?
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Hi Henrik,

Sorry if I muddied the waters . . . .

These Hyper-V Tasks are normally run locally (The VMs are hosted on the same physical server as VisualCron runs on). This Server is Windows Server 2012 R2, and these tasks had been quite happy for a period of Time before the latest KBs from Microsoft.

i.e. This is all on the Physical Hyper-V Host Machine running VisualCron 7.1.9 locally

VM Stops from VisualCron Hyper-V Tasks Worked OK - 6:00 pm
Microsoft KBs Applied using VisualCron - 1:00 am
VM Starts from VisualCron Hyper-V Tasks - Failed - 3:00 am

Subsequent testing of a Test VM on that host could not be stopped or started using the VisualCron Hyper-V Tasks - Failed with the Error in the Screen Prints.
Workaround (Using PowerShell) implemented.

The Workarounds (Using Stop-VM and Start-VM from a powershell task instead of the delivered Hyper-V tasks in VisualCron) are also running locally, from VisualCron 7.1.9.

As this is a Server in constant use I didn't want to mess with a Beta there or try KB Uninstall combinations with reboots so reverted to PowerShell to isolate the issue. If you can't replicate then please just let me know . . . . we have had some (IE, Client & Server) grief from KB's of late . . .

--- *** ---

I did attempt the same operations from *remote* so I could try the latest Beta Client . . . . but the error was different. Probably should have left that out ! . . . Not something we normally do. . . .
Could you post your settings of that Task?
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Also, have you tried to reboot the whole server since the update?
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Yes we always reboot after OS Updates.

We have since done a second reboot, edited those tasks seem OK again now . . . .

We did not have any indication from Hyper-V or from stopping and starting the VM's direct, or via powershell that there was any issue. . .

Task Screen Shots included, note these have variables in them (Other Job Tasks use the server name also).


KJDavie attached the following image(s):
Strange - but I am glad it is working now. Thanks for the report.
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