virtualbox.org

I have a problem with virtualbox after formatting the computer. I create a virtual machine and as soon as I try to install an operating system, the ram assigned to the virtual machine becomes saturated preventing the installation (I see the saturation from the windows taskmanager by looking at the virtualbox process). I tried to increase the ram but any assigned size is saturated. Before formatting the pc everything was working correctly. thanks

Start the VM from full power off, not save-state. Run until you see the problem happen, then shut down the VM from within the VM OS if possible. If not possible, close the Virtualbox window for the VM with the Power Off option set.

Please right-click the VM in the main Virtualbox window's VM list, choose Show Log. Save the far left tab's log, zip the log file, and post the zip file, using the forum's Upload Attachment tab.

Also, please explain which 'computer' you formatted: the physical host PC or the VM.

I have attached the required file. I formatted the physical pc. Thank you

After several attempts I understood the problem, I write the explanation in case it can be useful especially for developers.
The problem arises by formatting the physical computer and installing Windows 11. If you format the physical computer by installing Windows 10 and then upgrading to Windows 11 the problem does not arise. I also noticed that by installing Windows 11 directly the "enable VT-x / AMD-V" item remains disabled while installing windows 10 and upgrading to Windows 11 is available.

Anyone have any suggestions please?
Today I ran into the same problem switching from a windows 11 home to pro license. I do not know what to do

The log from earlier shows a host Hyper-V service running and preventing Virtualbox from running completely.

Start the guest from full normal shutdown, not save-state. Run until you see the problem happen, then shut down the guest from within the guest OS if possible. If not possible, close the Virtualbox window for the guest with the Power Off option set.

Right-click the guest in the main Virtualbox window's guest list, choose Show Log. Save the far left tab's log. Search the log for these words:

Attempting fall back to NEM

If these words are in your guest's vbox.log, Hyper-V is enabled. See HMR3Init: Attempting fall back to NEM (Hyper-V is active).