Virtualbox “Callee RC: REGDB_E_CLASSNOTREG” (0x80040154)?


I was getting the Virtualbox problem

Callee RC: REGDB_E_CLASSNOTREG” (0x80040154)

all of a sudden. Problem started on VirtualBox 4.3 (I think). I upgraded to version 5 hoping to fix it but had no luck at that point.

asked on Stack Overflow Jul 26, 2015 by mrpalferink • edited Jul 26, 2015 by Holger Just

9 Answers


My solution: Check your directory C:\Users\yourname\.VirtualBox\ (yourname is in fact your username.)

On my PC there was a VirtualBox.xml with size of 0 Kb. Also there was a VirtualBox.xml-prev with a size of 3 Kb. Dates where somewhere around the time the problem started...

Renaming the VirtualBox.xml-prev one to the VirtualBox.xml SOLVED my issue.

For those without an xml file, here is my xml file, hopefully it helps .....

<?xml version="1.0"?>

<!-- ** DO NOT EDIT THIS FILE. ** If you make changes to this file while any VirtualBox related application ** is running, your changes will be overwritten later, without taking effect. ** Use VBoxManage or the VirtualBox Manager GUI to make changes. -->

-<VirtualBox version="1.12-windows" xmlns="">



<ExtraDataItem value="general,system,previewClosed,display,storage,audio,network,usb,sharedFolders,description" name="GUI/DetailsPageBoxes"/>

<ExtraDataItem value="m=59397901-1440-48ea-8781-6f86d06c7fbb" name="GUI/GroupDefinitions/"/>

<ExtraDataItem value="m=Sharepoint" name="GUI/LastItemSelected"/>

<ExtraDataItem value="415,153,770,550,max" name="GUI/LastWindowPosition"/>

<ExtraDataItem value="D:/virtualbox" name="GUI/RecentFolderHD"/>

<ExtraDataItem value="D:\virtualbox\Sharepoint.vdi;" name="GUI/RecentListHD"/>

<ExtraDataItem value="334,1261" name="GUI/SplitterSizes"/>

<ExtraDataItem value=",confirmGoingScale,remindAboutAutoCapture,remindAboutMouseIntegration,showRuntimeError.warning.HostAudioNotResponding,confirmInputCapture,warnAboutInaccessibleMedia" name="GUI/SuppressMessages"/>

<ExtraDataItem value="53" name="GUI/UpdateCheckCount"/>

<ExtraDataItem value="1 d, 2015-08-19, stable, 5.0.0" name="GUI/UpdateDate"/>



<MachineEntry src="D:/virtualbox/Sharepoint/Sharepoint.vbox" uuid="{59397901-1440-48ea-8781-6f86d06c7fbb}"/>









<DHCPServer enabled="1" upperIP="" lowerIP="" networkMask="" IPAddress="" networkName="HostInterfaceNetworking-VirtualBox Host-Only Ethernet Adapter"/>



<SystemProperties exclusiveHwVirt="false" LogHistoryCount="3" webServiceAuthLibrary="VBoxAuth" VRDEAuthLibrary="VBoxAuth" defaultHardDiskFormat="VDI" defaultMachineFolder="C:\Users\yourname\VirtualBox VMs"/>



answered on Stack Overflow Jul 26, 2015 by mrpalferink • edited Aug 18, 2015 by mrpalferink

I had the error...

Failed to create the VirtualBoxClient COM object. The application will now terminate. Callee RC: REGDB_E_CLASSNOTREG (0x80040154)

...when starting VirtualBox as normal user. Starting as administrator worked on the other hand.

System: Windows 8, VirtualBox 5

Actually, the issue "suddenly" appeared after I played around with raw disk accesses. During these test, I re-installed VirtualBox as administrator.

What people not always know is that the registry has also an access right management, like files. Right-click on a folder to access the Autorisations window to display them.

When I re-installed as administrator, the registry keys where created with an admin level access. By this, I wasn't able anymore to start VirtualBox as non-admin.

Re-installing as normal user did not solve the problem. Probably because some admin-level keys could not be deleted.

Solution that worked for me:

  • Back-up .VirtualBox (optional, as all backups are :-)
  • Uninstall VirtualBox
  • Open Registry Editor regedit.exe as administrator.
  • Delete all remaining VirtualBox keys (especially the .NET, driver registrations, Compatibility Manager settings)
  • Reinstall VirtualBox using a user account.


I did not test escalating the VirtualBox uninstaller process to administrator level with sysinternals. That might work as well.

Be careful with regedit. The GUI is quite '90s. Good to know: CTRL+F searches below the currently selected key, so be sure to go to the top when start searching.

I had one key for an USB driver that I wasn't able to delete due to access rights problems. Finally, this was not needed anyway.

Please don't forget to change access rights on VirtualBox disk files when they have been created with VirtualBox running as administrator.

answered on Stack Overflow Aug 28, 2015 by Imifos • edited Aug 28, 2015 by Imifos

Renaming the VirtualBox.xml-prev one to the VirtualBox.xml solved my issue.

answered on Stack Overflow Feb 29, 2016 by John P • edited Feb 29, 2016 by Adam

After you upgrade to VirtualBox-5.0.8-103449 started getting error: Virtualbox "Callee RC: REGDB_E_CLASSNOTREG" (0x80040154)

No advice on the Internet did not help.

It helped only delete the entire contents of the folder "C:\Users\"user"\. VirtualBox" and then restart Oracle VM VirtualBox shortcut on the desktop.

Apparently when you remove the previous version of Virtualbox folder "C:\Users\"user"\.VirtualBox" is removed.

As the contents of the folder should be removed manually after reinstalling VirtualBox, as well as in case of damage VirtualBox, for example due to lack of space on the hard disk.

Not to be confused with the folder "C:\Users\"user"\VirtualBox VMs"

This folder appears later, only after the establishment has a particular virtual machine.

sorry for machine translation.

answered on Stack Overflow Nov 8, 2015 by Алексей Ерш • edited Nov 8, 2015 by Алексей Ерш

In my case this error was caused by a zero-byte truncated VirtualBox.xml in the user's .VirtualBox folder. I found out after downgrading to 4.x and getting a more descriptive error message regarding a missing < tag.

answered on Stack Overflow Apr 29, 2016 by ZeKritik • edited Apr 30, 2016 by Bono

As I already suggested on superuser, as of today (09/09/2015).

Upgrade to the new version that was released.You can find it here

There have been some changes concerning the Windows 10 Problems.

answered on Stack Overflow Sep 9, 2015 by p2k • edited Mar 20, 2017 by Community

The solution is in the last paragraph.

I happened to have a different cause for the same error message under VirtualBox 5.0.20.
So I temporarily installed VirtualBox 5.1.10 which tries to analyse the situation and gives more info about probable culprit.

In my case the error message from VB 5.1.10 looked like following:

Failed to instantiate CLSID_VirtualBox w/ IVirtualBox, but CLSID_VirtualBox w/ IUnknown works.
PSDispatch looks broken by the 'xxx' ({11B6009E-3F04-4478-A807-30FBD579FC07}) program, suspecting that it features the broken oleaut32.msm module as component {997FA962-E067-11D1-9396-00A0C90F27F9}.
We suggest you try uninstall 'xxx'.
See also .

Result Code:
E_NOINTERFACE (0x80004002)
IVirtualBoxClient {d2937a8e-cb8d-4382-90ba-b7da78a74573}

Where 'xxx' is here a placeholder name for a specific program name it mentions and suggests to uninstall. (The specific name in my case is not important here).

So I did uninstall the specific program the new VirtualBox version accused, and after that VB started working again. Then I reinstalled the old VB version 5.0.20 I needed to continue using and all was well.

answered on Stack Overflow Jan 23, 2017 by Roland Pihlakas • edited Feb 10, 2017 by Roland Pihlakas

After some researching I found this thread with the step:

find C:\Program Files\Oracle\VirtualBox\drivers\vboxdrv\VBoxDrv.inf right click and select Install
answered on Stack Overflow Mar 28, 2019 by hestellezg

I had this same issue, I believe something corrupted whilst shutting down without correctly closing connections and I couldn't boot VB.

Tried all of the solutions above but none of them worked.

Without Uninstalling I went to the virtual box website and grabbed the most recent version and installed over the top and VB jumped into life.

Version 6.0.14 From 6.0.10

answered on Stack Overflow Oct 16, 2019 by TattooedGun

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