virtualbox.org

I'm running Windows 8.1 Pro, 64bit. 16GB RAM. My laptop crashed and I took the opportunity to add a second hard drive, replacing the optical. My primary (boot) drive is an SSD (500GB).

1) I added a 1TB SSHD for my second drive. Initially for setup I connected the drive using a USB to SATA cable (http://www.apricorn.com/sata-wire-3.html). Installed VirtualBox and setup several 64bit VMs (linux and windows).

2) My hard drive caddy arrived in the mail (http://www.newmodeus.com/) so I moved the second hard drive to the caddy, changing the connection from USB to SATA.

3) After booting up my VMs won't load. I get the error "VT-x is not available. (VERR_VMX_NO_VMX)"

4) I tried adding new VMs, hoping I could just point them back to the existing image. I cannot add 64bit VMs, they are all missing from the menu now. Which I assume is the real heart of the problem which booting the old ones.

5) I rebooted into BIOS and virtualization is enabled. Virtualization IS ENABLED.

So.... I have no idea what's going on. Help appreciated. I'm really confused how changing the interface for this hard drive would have this effect. And note, this is the secondary drive ONLY. The boot drive never changed. And VB loads off of C:\, so I'm completely perplexed. I do have the default storage folder for VB set to Y:\, which is the secondary drive.

Don't everybody answer at once

Bump please

No idea at all since this should not have a baring on whether VT-x is available or not.

Do you have anything else running that is using hardware virtualization IE: Hyper-V?

Before even seeing your post I tried some other things. Uninstalling Hyper-V fixed the problem. This all is extremely odd though because as previously described, nothing new was installed. All I did was switch from USB to SATA for the drive. Hyper-V was installed before and there was no issue. Removing it did in fact fix the issue though. Other threads I read said the issues with Hyper-V were sorted out after version 4.3.9 and beyond. But that doesn't seem to be the case.

Thanks!

The only way the issue will ever be sorted out concerning Hyper-V is when Microsoft decides to not make it take complete control and play nice with other apps trying to use it.

I can't believe that you ever had VirtualBox with working hardware virtualization on a host running Hyper-V. It simply cannot happen. Perhaps you were running a 32-bit guest?

Because of the way Hyper-V works, the hypervisor is loaded before the OS loads (the host OS is in fact running on top of the hypervisor, not directly on the hardware), so there is never a time after boot when hardware virtualization is available to any program running on the Windows host.