Virtual Machine Bus (vmbus) Service Defaults in Windows 7

Virtual Machine Bus by Microsoft Corporation.

The Virtual Machine Bus service does not exist in:

Default Settings

Startup type:
Windows 7 ProfessionalManual
Windows 7 UltimateManual
Windows 7 EnterpriseManual
Windows 7 Professional SP1Boot
Windows 7 Ultimate SP1Boot
Windows 7 Enterprise SP1Boot
Display name:Virtual Machine Bus
Service name:vmbus
Service type:kernel
Error control:normal
Group:Extended Base
Registry key:HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\vmbus

Default Behavior

Virtual Machine Bus is a kernel device driver. It doesn't exist in Windows 7 Starter SP0, Windows 7 Home Basic SP0, Windows 7 Home Premium SP0, Windows 7 Starter SP1, Windows 7 Home Basic SP1, Windows 7 Home Premium SP1. This service won't be started if the user doesn't start it in Windows 7 Professional SP0, Windows 7 Ultimate SP0, Windows 7 Enterprise SP0. This service is being loaded by Boot Loader before Kernel initialization in Windows 7 Professional SP1, Windows 7 Ultimate SP1, Windows 7 Enterprise SP1.

If Virtual Machine Bus fails to start, Windows 7 attempts to write the failure details into Event Log. Then Windows 7 startup should proceed and the user should be notified that the vmbus service is not running because of the error.

Restore Default Startup Configuration of Virtual Machine Bus

1. Run the Command Prompt as an administrator.

2. Depending on the version of your operating system, copy the commands below, paste them into the command window and press ENTER.

For Windows 7 SP0 Enterprise, Windows 7 SP0 Professional, Windows 7 SP0 Ultimate:
sc config vmbus start= demand

For Windows 7 SP1 Enterprise, Windows 7 SP1 Professional, Windows 7 SP1 Ultimate:
sc config vmbus start= boot
sc start vmbus

3. Close the command window and restart the computer.

The vmbus service is using the vmbus.sys file that is located in the C:\Windows\system32\DRIVERS directory. If the file is removed or corrupted, read this article to restore its original version from Windows 7 installation media.