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VMware Networking Issues with Windows 7

If you need a Firewall between the physical host and its guest virtual machines, this workaround is not for you.

The problem is that on Windows 7 (x86/x64) the VMware virtual adapters and subnets are found and reported as “Unidentified Network”. This means that the built-in Windows Firewall can only treat the VMware networks, and thus the guest VMs, as type Public.

When the network type is set to Public, the Windows Firewall by default blocks Microsoft File & Print, and other most other network traffic, which effectively prevents useful direct communication between the physical host and its VM guests. You might, if allowed, disable the Firewall or configure exception rules for the VMware virtual subnets and/or hosts. Disabling the Firewall for all public networks is a bad security practice and managing the Windows Firewall is a tedious task that still leaves potential security holes.

Below are the instructions from the VMware Knowledge Base Article 1004813 that I used to change the VMware virtual network adapters to be endpoints. Endpoints do not show up in the “Network and Sharing Center” are also excluded from control of the Windows Firewall. This makes it easier to manage the Firewall rules and Home, Work, and Public network types for real, physical adapters.

This work around solution can be used until VMware updates their networking technology to meet current operating systems standards.

# VMware KB Article: 1004813
# Updated: Apr 29, 2010

Redefine the VMware virtual NICs as endpoint devices

This procedure is permanent and allows for the continued use of Bridged, NAT, and Host Only networking. However, doing this causes the VMware virtual NICs to disappear from the Network and Sharing Center, even though they remain visible under Network Connections. This also causes the VMware virtual NICs to be exempt from all Windows Firewall access rules. When implemented, the control of virtual machine network access must be done from the guest operating system of each virtual machine. This bypasses the default security model of Windows Vista with respect to the the VMware virtual NICs, and the implications of using this procedure must be carefully considered.

To redefine the VMware virtual NICs as endpoint devices:

  1. Click Start > Run.
  2. Type regedit and click OK.
  3. Double-click HKEY_LOCAL_MACHINE>System>CurrentControlSet>Control>Class>{4D36E972-E325-11CE-BFC1-08002BE10318}.
    Caution: VMware recommends that you back up this registry key before proceeding:
    1. If {4D36E972-E325-11CE-BFC1-08002BE10318} is not still highlighted, click it.
    2. Click File > Export.
    3. Pick a location and name for the Registration File (*.reg).
    4. Click Save.
  4. Click 0000.
  5. Look at the content of the Data field associated with the DriverDesc entry.
  6. If you see VMware Virtual Ethernet Adapter for VMnetx , where x is replaced by a number, then:
    1. Right-click an empty space in the right content pane.
    2. Click New > Dword.
    3. Type *NdisDeviceType
      and press Enter.
      Note: Ensure to include the asterisk (*) at the beginning of the entry.
    4. Double-click *NdisDeviceType.
    5. Type 1 and press Enter.
  7. Repeat steps 4-6, replacing 0000 in step 4 with the next entry in numerical order, until you have reached the end of all numerical entries.
  8. Follow the Disable the VMware virtual NICs section of this article above.
  9. Repeat step 8 but click Enable this network device instead.

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