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Windows device manager shows yellow exclamation for VMCI device (1023129)

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In a Windows virtual machine, the desktop toolbar or Device Manager shows a yellow circle with exclamation mark (yellow bang) indicating a device problem. This might indicate that the VMware VMCI (virtual machine communication interface) Bus Device driver is missing. The incomplete VMCI device might be displayed in the Other Devices section of Device Manager as the Base System Device, a generic Windows name.

The VMCI device is used for host-to-guest communications.


The VMCI Bus Device driver is available by installing VMware Tools. VMware Tools packages are available locally on ESXi hosts. VMware Fusion and Workstation can install VMware Tools over the Internet. When you use the menus to initiate an install, the software makes a secure network connection and mounts VMware Tools as a virtual CD. You do not need a physical CD.

With VMware Fusion or Workstation, click Virtual Machine (VM) > Install VMware Tools. With ESXi, run the vSphere Client and click Inventory > Virtual Machine > Guest > Install/Upgrade VMware Tools. Follow the on-screen instructions displayed during the VMware Tools installation. The VMCI driver is installed by any option you select during installation, such as Typical, Complete, or Custom. The Install VMware Tools menu item may be grayed out while downloading and installing, or if no network connection is found.

After installing VMware Tools, open the Device Manager to verify that the yellow warning has disappeared, and that the VMware VMCI Bus Device appears under the System Devices section of Device Manager.

Virtual hardware version 7 virtual machines have the VMware VMCI Bus Device enabled by default, but the device driver is not pre-installed; it is obtainable only through the VMware Tools installer. The VMCI device cannot be removed from virtual hardware version 7 virtual machines.

For Windows 98 and Windows 98SE, there is no support for the VMCI device in VMware Tools. One workaround is to disable the VMCI device using the Device Manager so that it is ignored by Windows, and diagnostic tools stop reporting errors. Another workaround is to downgrade the virtual machine to virtual hardware version 4.

Windows 8 and Windows Server 2012 are supported with VMware Tools in Workstation 9.x and later, Fusion 5.x and later, and ESXi 5.1 and later.

The yellow warning could appear for reasons other than the lack of a VMware Tools driver. The dialog box for the device might show a numeric code, which you can check against the list of error codes in Microsoft Knowledge Base article 310123.

In some cases, uninstalling the device with the Device Manager and performing a scan for new hardware resolves the issue, as suggested under error Code 19.

For more information about VMware Tools, see Overview of VMware Tools (340).

For information about VMCI programming, see the VMCI Sockets Documentation.

Note: The preceding links were correct as of November 10, 2015. If you find a link is broken, please provide feedback and a VMware employee will update the link.

Additional Information

For translated versions of this article, see:


vmci-device  vmci-device-flagged  device-manager-yellow-flag

Update History

08/25/2014 - Updated for Fusion 7.x 02/12/2014 - Updated for Workstation 11.x 02/12/2014 - Updated for Player 7.x

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  • 474 Ratings