Weird starting behaivor + error launching guest VM

[CHoceur]

Hi guys,

I did some research here and in google, but did not really find a solution to my problem:
I was using Virtual Box on my Windows system for a long time with no problem. Suddenly with no known reason to me a weird bug appeared. I did not install a new app/toll, no updates by me, no changes in bios, drivers etc.
When I start Virtual Box it seems that nothing happens like the app would not open. But if you check the task manager you can see the 3 apps started:
- VBoxSDS.exe
- VBoxSVC.exe
- VirtualBox.exe

If I kill all the processes and try to start again, the same happens. Only if I do a full restart of Windows and also not every time(!) the app will start. Now if I get here, I have a new problem: Any Vm I try to start gives me following error:
Not in a hypervisor partition (HVP=0) (VERR_NEM_NOT_AVAILABLE).
AMD-V is disabled in the BIOS (or by the host OS) (VERR_SVM_DISABLED).

I uninstalled the app and installed the newest version, but it did not help. Does this make sense to anybody?

Here some hardware specs, I can provide more detailed if necessary:

CPU Name AMD Ryzen 5
Specification AMD Ryzen 5 1600 Six-Core Processor
Package Socket AM4 (1331)
board vendor Micro-Star International Co. Ltd.
model B450M-A PRO MAX (MS-7C52)
RAM DDR4 16GB
Windows Version Microsoft Windows 10 (10.0) Professional 64-bit (Build 18363)
GFX NVIDIA GeForce GTX 1650 SUPER

[scottgus1]

Try unplugging all USB devices from the host PC except basic keyboard and mouse, see if Virtualbox starts. If it does, then one of the USB devices is up-ending Virtualbox.

Regarding the AMD-V error, see I have a 64bit host, but can't install 64bit guests

[CHoceur]

Hey scottgus,

thanks for the 2 advices. The trick with removing USB devices really worked! Regarding the not starting VMs I read the linked post very carefully and did all steps. I also checked the bios again and AMD-V is on, on Windows the tool CPU-Z also confirms this. But there is no success, I still get this error. My both VMs are configured as 32bit (Windows 7 + some Linux Lamp distribution "bitnami"). I am afraid that I need to reinbstall Windows to solve this

[scottgus1]

Once you pin down which USB device(s) cause the seize of the main Virtualbox window, you might be able to plug the devices in after Virtualbox has been started.

If your BIOS definitely has AMD-V on, it's being used by some other app, as indicated in the linked tutorial. Getting rid of that app, or finding the 'use virtualization' setting in the app might let Virtualbox start working. Sometimes reinstalling that app after Virtualbox is working doesn't kill Virtualbox again, meaning coexistence could be possible. We can't tell what app is interfering, though.

If you're thinking of a full OS reinstall, then after the OS install Virtualbox first, confirm it's running well, then try one other app at a time, with a reboot, then see if Virtualbox still runs. You might find the offending app this way. You could also do this on a different host disk as a test first.