"Failed to acquire the VirtualBox COM object."

[tot94]

Hello,

I have a problem launching VirtualBox..
I don't know why this error message suddenly appears :



I have uninstall et install again, no result..

Have you got any solution ??

Regards,

[mpack]

That error message implies that VirtualBox has not been installed.

Describe how you are installing VirtualBox? Obviously if you are doing it wrong then repeating the process will not help.

The right way is to install as the correct user (not the "Admin" user, or the "Administrator" user), but use "Run as administrator" to run the installer.

[tot94]

I download :

VirtualBox 5.1.6 for Windows hosts x86/amd64

Then I run it as administrator.

Again the same error message appears...

Start tag expected, '<' not found.
Location: 'C:\Users\T\.VirtualBox\VirtualBox.xml', line 1 (0), column 1.
F:\tinderbox\win-5.1\src\VBox\Main\src-server\VirtualBoxImpl.cpp[549] (long __cdecl VirtualBox::init(void)).


Result Code:
E_FAIL (0x80004005)
Component:
VirtualBoxWrap
Interface:
IVirtualBox {0169423f-46b4-cde9-91af-1e9d5b6cd945}
Callee:
IVirtualBoxClient {d2937a8e-cb8d-4382-90ba-b7da78a74573}

[scottgus1]

Then I run it as administrator.

As in this?

Then I right-click-choose "run as administrator" in the popup menu

[tot94]

Log detail :

Start tag expected, '<' not found.
Location: 'C:\Users\T\.VirtualBox\VirtualBox.xml', line 1 (0), column 1.
F:\tinderbox\win-5.1\src\VBox\Main\src-server\VirtualBoxImpl.cpp[549] (long __cdecl VirtualBox::init(void)).

Result Code: E_FAIL (0x80004005)
Component: VirtualBoxWrap
Interface: IVirtualBox {0169423f-46b4-cde9-91af-1e9d5b6cd945}
Callee: IVirtualBoxClient {d2937a8e-cb8d-4382-90ba-b7da78a74573}

[scottgus1]

The little picture posted above does seem to show right-click-run-as-admin being used.

The "Start tag expected, '<' not found" sounds like a possibly malformed master guest registry.
Here's an idea:

reboot your host.
go to c:\Users\{your-user-name}. Inside that folder will be a ".Virtualbox" folder. Move this .Virtualbox folder onto the desktop.

Now try running Virtualbox. If the GUI window comes up and you have no guests showing, the I would diagnose a bad Virtualbox.xml in the .Virtualbox folder

Post back if Virtualbox launches with no guests listed.

[tot94]

You are right, now it works !
What I am suppose to do now ? I let the folder on the folder ?

I have no guest list because I have unistall VirtualBox before..

[scottgus1]

OK, so I would now reboot the host again to clear out any running Virtualbox processes.

Then go back to c:\Users\{you} and delete the new .Virtualbox folder.

Copy the .Virtualbox folder froom the desktop to the c:\Users\{you} folder. Keep the copy on the desktop as a backup, because we're going to footle about with the files in the c:\Users\{you}\.Virtualbox folder

In the c:\users\{you}\.Virtualbox there is very likely a "VirtualBox.xml" and a "VirtualBox.xml-prev". Rename "VirtualBox.xml" to "VirtualBoxbad.xml-bad" and then rename "VirtualBox.xml-prev" to "VirtualBox.xml".

Fire up Virtualbox again and let us knw what happens.

[scottgus1]

I just noticed this part:

I have no guest list because I have unistall VirtualBox before..

If you had no guests before, then just deleting the .Virtualbox folder and starting Virtualbox will let you get going.

Keep in mind that any Preferences changes in the main Virtualbox window will need to be re-set.

If you do get a guest set up and the same "Start tag expected, '<' not found" error occurs again one day, you can re-register the guests in the refreshed Virtualbox by finding and double-clicking the guests' .vbox files.

[tot94]

You procedure works well
I thought the VirtualBox uninstall would have delete my hosts but instead they appear as inaccessible..
I will delete them again
Thank you

[socratis]

I thought the VirtualBox uninstall would have delete my hosts guests

I corrected the hosts/guests, since host is your physical computer, guests are the virtual ones. But that's not the point. Guests are "documents", "data". Uninstalling LibreOffice or MicrosoftOffice does not delete your documents, right? Same with VirtualBox. Uninstalling VirtualBox does not delete your guests (your VMs).

[elisatih]

I have the same problem.

I try this:
I remove C:\Users\<username>\.VirtualBox
and
SOLVED! My VirtualBox apps is run...

[niceguy42]

Log detail :

Start tag expected, '<' not found.
Location: 'C:\Users\T\.VirtualBox\VirtualBox.xml', line 1 (0), column 1.
F:\tinderbox\win-5.1\src\VBox\Main\src-server\VirtualBoxImpl.cpp[549] (long __cdecl VirtualBox::init(void)).

Result Code: E_FAIL (0x80004005)
Component: VirtualBoxWrap
Interface: IVirtualBox {0169423f-46b4-cde9-91af-1e9d5b6cd945}
Callee: IVirtualBoxClient {d2937a8e-cb8d-4382-90ba-b7da78a74573}

This worked great for me but seems like a band-aid. Is there a better solution or a reason why this happens? I have uninstalled and reinstalled as admin and this kept happening.

[mpack]

We can't tell you why files on your host are being corrupted. It's not something that we see generally.

[Katarina Player]

I got this problem too, my solution was that I got into task manager and ended all processes that were related to Virtualbox, after that I just started it again and it worked