[Solved] All virtual machines worked yesterday but not today

[PLCman]

Hi

All of my virtual machines have stopped working with the error message attached. As far as I know nothing has changed on my Windows 8.1 installation, no new software installed.

Can anyone tell me what has gone wrong?

[socratis]

Please remove the two partial logs and replace them with a ZIPPED VBox.log. And add please the VBoxHardening.log. ZIPPED as well. Try to save a (virtual) tree or two...

[PLCman]

Hi

Thanks for getting back to me.

I don't seem to have a VBoxHardening.log

[socratis]

I don't seem to have a VBoxHardening.log

Are you sure? It should be in the same directory as the rest of the logs. Well, maybe you don't have it. I don't remember when it was implemented. But you are running:

VirtualBox VM 4.3.18 r96516 win.amd64 (Oct 11 2014 13:21:57) release log

That's a way, way, way too old version of VirtualBox. You need to update to the latest and greatest, 5.1.28 as of this writing, or even the 5.2.0rc1, which is a step away from being declared 5.2.0.

1. Uninstall VirtualBox. Your VMs are going to be untouched. Reboot.
2. You may want to clean up your registry and/or filesystem at this point. CCleaner is a freeware utility that could help you. Mind the installation, it comes with "offers" from 3rd parties, known as "bundleware". Also, check out Device Cleanup program that helps you to remove any unused devices from your computer.
3. Download (if you haven't already) the latest VirtualBox and its matching ExtPack. Store them in a common location, i.e. not on "Desktop", or "Documents", but to "Public/Downloads" for example.
4. Locate the downloaded file in Windows Explorer. Right-click on the installer and select "Run-as-Administrator", even if you are the administrator. At the end of the installation, choose to "Start Oracle VM VirtualBox". Do not worry if your VMs do not show up.
5. If you're going to install the ExtPack, go to File » Preferences » Extensions. Click on the icon with the orange, down-pointing arrow on the right. Select the ExtPack from the previous steps.
6. Quit VirtualBox. Re-start VirtualBox as you would normally, i.e. from the Desktop shortcut or the Start menu.
7. Update the Guest Additions (GAs) in your guest(s), if the GAs are available for a specific guest.

Now, I wouldn't go any further analyzing your VBox.log, except a couple of basic things:

00:00:02.167991 Guest OS type: 'WindowsXP'
00:00:02.877196   RamSize         <integer> = 0x0000000200000000 (8 589 934 592, 8 GB)

You dedicated 8 GB of RAM to a 32-bit guest that can see ~3.5 GB tops. Do not assign that much RAM to your guest. Drop it down to ~3.5 GB.

00:00:02.877193   NumCPUs         <integer> = 0x0000000000000004 (4)
00:00:03.464738 Logical host processors: 8 present, 8 max, 8 online, online mask: 00000000000000ff
00:00:03.465148 Physical host cores: 4

You have assigned all your CPUs to the VM. The host is going to run low on resources, since VirtualBox cares about physical processors, not logical ones. See: CPU Cores versus threads.

Oh, and for the history, your guru meditation error is:

00:00:03.969290 !! Guru Meditation -4004 (VERR_VMX_INVALID_VMXON_PTR)

[PLCman]

Many Thanks socratis!

Finally got around to taking your advice and all of my VM's are working again.

Thanks for your advice on my VM settings aswell.

[socratis]

I have to admit I'm not quite sure which one of the changes actually made it work, as this is a really rare Guru Meditation error. I think it was the VirtualBox upgrade. But, anyway glad you got it going, thanks for the feedback. Marking as [Solved].