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Since the installation of the October 2023 updates, random VM's fail to start after a reboot of the HyperV server (2019 DCE).
The error is: *<VMName> failed to start.
Synthetic SCSI Controller (Instance ID ....): Failed to Power on with Error 'Incorrect function.'.
Attachment '<path to vhdx file>' failed to open because of error: 'Incorrect function.'.*
To solve the problem, I have to:
After this rename, the VM starts without a problem. Yesterday I had 2 VMs with the problem, today 6 VM's had the problem.
The strange thing is that everything works after I rename the vhdx file.
Is anything known about this - is there a solution?
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I'm having the same issue with Server 2022. I uninstalled the update to get back up and running but might try reinstalling and trying the rename trick you mentioned.
The rename tricks only works until the next reboot or the next shutdown of the machine.
After that you have to do it again. Only uninstalling the updates work.
Sometimes I truly hate MS... man, you saved my life
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We figured out the following:
only standalone VM's are affected not clustered VM's
affected VM's have .mrt and .rct File in addition to the .vhdx
in your case they were created by DPM
Fast workaround: delete the .mrt and .rct file
negative Side Effect: error in DPM --> Recovery Point creation failed and backup needs consistency check.
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Thank you for this suggestion. I restarted my host computer early this morning to complete updates and one of my Hyper-V VMs would not start because of a similar error (Synthetic SCSI Controller failed to power on with error the parameter is incorrect). Deleting he .mrt and .rct file corrected the problem at least for now.
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Deleted the MRT & RCT files worked for me. Sever 2019
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I have the exact same problem on two Hyper-v host servers so far. In both cases the attached drive is used by Windows Server Backup in the Guest OS. Your trick to rename the disk works but this is clearly some major glitch in the matrix.
I solved the problem by uninstalling the Windows Update.
Hopefully the cause will be solved in the November updates.
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We had the same issue and renamed the vhdx files which fixed the problem. I tried renaming back and the issue returns. In our environment we don't encounter the issue again after a reboot of the affected VM's or hosts.
