If you’ve ever experienced temporary loss of connectivity or other weird issues when you run virtual machines in VMWare Workstation and/or Virtual Box then you’re in for a treat. The issue is to my knowledge specific to Intel network cards. I’m not sure how relevant it is but I was running Windows 7 SP1 64-bit with the most recent drivers at the time when I started noticing the issue.

This is about two modes that you can set via the registry for your network card to fix the issue. What you need to use depends on your network card.

Allow tagged frames to be passed to your packet capture software by going into the registry and either add a registry dword and value or change the value of the registry key. The registry change required is determined by the driver in use

Registry Key          Adapter Driver
MonitorModeEnabled    e1g, e1e, e1y
MonitorMode           e1q, e1k, e1c, e1d, ixe, ixn, ixt

To solve my issue with my Intel PRO/1000 PT Dual Port Server card I added the DWORD key “MonitorMode” to the following registry path

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Class\{4D36E972-E325-11CE-BFC1-08002BE10318}\0007

with a value of “2” to fix my issue. Note: Due to my dual port adapter I had two entries for my 1 physical network card.

Anyways, head on over to the Intel support article for a detailed description on how to correct this issue for yourself.

Good luck!

// CrashMAG