Unusably slow Windows 7 guest on Windows 10?

[system11]

I've installed VirtualBox 6.1.34, and while my RHEL and XP VMs seem to work fine, the Windows 7 install I'm trying to complete is so slow it has taken 2 hours (so far) for the post-installation boot. Looking at the session information the CPU is basically locked at 100%. Disk, RAM usage and network are virtually flat. The only other stat on there is 'vm exits' at 2.28 million.

I gave the W7 machine 8gb of RAM and 2 virtual CPUs, my host has 64gb and an 11th gen i9.

Does anyone know what I've done wrong?

Have attached a log from the currently "running" VM.

[BillG]

You have these lines in your log, which indicate that you have the Windows hypervisor platform enabled.

00:00:02.173398 HM: HMR3Init: Attempting fall back to NEM: VT-x is not available
00:00:02.205658 NEM: info: Found optional import WinHvPlatform.dll!WHvQueryGpaRangeDirtyBitmap.
00:00:02.205730 NEM: WHvCapabilityCodeHypervisorPresent is TRUE, so this might work...

Running VirtualBox with the Windows hypervisor loaded is still not working very well.

[AndyCot]

@billg, The

Running VirtualBox with the Windows hypervisor loaded is still not working very well.

is applicable for 6.1.34, but not for the 6.1.35 r151573 test build.

@system11, If you need Hyper-V then grab the 6.1.35 r151573 test build and use it, but if you do not need Hyper-V then the instructions for disabling it as in the following post:
viewtopic.php?f=25&t=99390

[scottgus1]

If you do try the test build, 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.

[system11]

That's the strange thing, Hyper-V was disabled in the windows features list. I had a similar issue with VMware, even though it was disabled and the machine rebooted (reconfigures itself) some element of Hyper-V was still visible and it forced me to install an extension to interface with it.

Edit: I just read that page linked above - it'll be the core protection part of windows defender - that's still turned on.... Thanks, I'll see what happens turning it off.

[mpack]

That's the strange thing

Not really. It is well known, otherwise the instructions for turning it off for real would hardly need the whole FAQ article referenced above!

That Windows option just turns off one user level feature, not the entire underlying mechanism.