﻿id	summary	reporter	owner	description	type	status	component	version	resolution	keywords	cc	guest	host
12744	Error 0x000000C4 when booting Windows 7 x64 (Ubuntu 12.04 x64 host) after update to 4.3.8-92456 [FIXED in SVN]	uchuujin		"Hello!

I just encountered the following error:

- Host OS: Ubuntu 12.04 x64
- Updated Virtualbox 4.3.6-91406 to 4.3.8-92456 from the official Virtualbox repository
- Updated the guest additions too
- Started Windows 7 x64 virtual machine (was running fine before)
- The machine crashed with error STOP: 0x000000C4 upon startup

After that, I tried the following:
- the solution suggested in https://www.virtualbox.org/ticket/11841 (VBoxManage setextradata [vmname] VBoxInternal/CPUM/CMPXCHG16B 1)
- Downgrading guest additions to 4.3.6-91406
- Removing guest aditions altogether
- Turning off hardware acceleration (graphics, CPU)

None of this works. My virtual machine crashes everytime, so I cannot use it anymore.

Please find a capture of the error message and Vbox.log attached."	defect	closed	other	VirtualBox 4.3.8	fixed			Windows	Linux
