Hi,
Host OS: Windows 7 Ultimate x64 on SSD system disk.
PC Specs: Intel Core i7 3770K on ASRock Z77 OC Formula with 16GB DDR3, GTX470
VirtualBox version: 4.3.12 r93733 with Extension Pack 4.3.12 r93733.
I've had a Windows 8.1 Pro x64 VM running on VBox 4.3 for a few days now with no issues at all.
However, this morning, the VM refused to boot saying VT-x was not enabled.
I checked via the VM settings but the whole "Acceleration" pane was disabled and not accessible. I was not able to resolve the issue even after rebooting my PC and explicitly enabling Intel Virtualization in the PC BIOS (it was on AUTO before - I set it to ENABLE).
I have since several times removed the VM completely and attempted to reinstall.
Every time, the VM hangs on the Windows 8 logo screen on install and then crashes with the Error 0x000000C4.
As found on VirtualBox community forums and on other sites, I have tried the SETEXTRADATA command via command prompt running as administrator, and have confirmed that the .vbox file has been changed and the string ExtraDataItem name="VBoxInternal/CPUM/CMPXCHG16B" value="1" appended in the <ExtraData> section.
However the VM still refuses to boot or reinstall. I have Ubuntu, Fedora and ZorinOS VM's all working perfectly.
The only change to my system that took place in the interim was that I installed Comodo Free Firewall last night. Seeing the problems I have been having with the VM since this morning, I uninstalled Comodo and rebooted thinking it might have something to do with my problems, but still no joy.
I am also uploading my .VBOX files before and after to show the changes that have been made by the SETEXTRADATA command.
Host OS: Windows 7 Ultimate x64 on SSD system disk.
PC Specs: Intel Core i7 3770K on ASRock Z77 OC Formula with 16GB DDR3, GTX470
VirtualBox version: 4.3.12 r93733 with Extension Pack 4.3.12 r93733.
I've had a Windows 8.1 Pro x64 VM running on VBox 4.3 for a few days now with no issues at all.
However, this morning, the VM refused to boot saying VT-x was not enabled.
I checked via the VM settings but the whole "Acceleration" pane was disabled and not accessible. I was not able to resolve the issue even after rebooting my PC and explicitly enabling Intel Virtualization in the PC BIOS (it was on AUTO before - I set it to ENABLE).
I have since several times removed the VM completely and attempted to reinstall.
Every time, the VM hangs on the Windows 8 logo screen on install and then crashes with the Error 0x000000C4.
As found on VirtualBox community forums and on other sites, I have tried the SETEXTRADATA command via command prompt running as administrator, and have confirmed that the .vbox file has been changed and the string ExtraDataItem name="VBoxInternal/CPUM/CMPXCHG16B" value="1" appended in the <ExtraData> section.
However the VM still refuses to boot or reinstall. I have Ubuntu, Fedora and ZorinOS VM's all working perfectly.
The only change to my system that took place in the interim was that I installed Comodo Free Firewall last night. Seeing the problems I have been having with the VM since this morning, I uninstalled Comodo and rebooted thinking it might have something to do with my problems, but still no joy.
I am also uploading my .VBOX files before and after to show the changes that have been made by the SETEXTRADATA command.
Attachments
My Computer
System One
-
- OS
- Windows 10 Pro x64
- Computer type
- PC/Desktop
- System Manufacturer/Model
- Self-built
- CPU
- Intel Core i7 8700K
- Motherboard
- Asus Maximus X Code
- Memory
- G.Skill TridentZ RGB DDR4-4000 F4-4000C18D-16GTZR (8GBx2)
- Graphics Card(s)
- Asus STRIX-GTX960-DC2OC-4GD5
- Sound Card
- Asus SupremeFX S1220
- Monitor(s) Displays
- Dell UP2716D
- Screen Resolution
- 2560x1440
- Hard Drives
- Drive #1 - Samsung SSD 840 PRO Series (238 GB)
Drive #2 - WDC WD2003FZEX-00SRLA0 (1863 GB)
Drive #3 - WDC WD2003FZEX-00Z4SA0 (1863 GB)
Drive #4 - NVMe Samsung SSD 970 (232 GB)
- PSU
- Coolermaster V1000
- Case
- Corsair Obsidian 450D
- Cooling
- Corsair H115i + 2x Corsair SP140 Red; Front case fans replaced with 2x Corsair AF140 Red LED
- Keyboard
- Logitech G213
- Mouse
- Logitech G102
- Internet Speed
- BSNL claims its 100Mbps FTTH
- Browser
- Maxthon 5
- Antivirus
- Avast Free