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I upgraded to windows 11 none of my Ubuntu VMs will start

If I add a CPU to 2 or more it starts but it gosh awful slow and I keep seeing a message that reads watchdog bug soft lockup cpu#0 stuck for 22s mysqld - Note its not always mysqld

I'm running Virtualbox 6.1.34r150636 (Qt5.6.2) How can I fix this

It's likely that Hyper-V was enabled during the upgrade. Right-click the guest in the main Virtualbox window's guest list, choose Show Log.

Search the far left tab's log for this text:

Attempting fall back to NEM

If you find it, Hyper-V is enabled. You'd then have two options:

1. Try the 6.1.35 test build, which is reported to work with Hyper-V enabled. Save the test build installer until you update again later. You'll need it if your host's MSI installation database goes south (they do) and the installer will not be available for download after the next even-number version gets released.
2. Turn Hyper-V off. See HMR3Init: Attempting fall back to NEM (Hyper-V is active).