Windows XP Mode and Hardware-Assisted Virtualization

Well, it looks like Microsoft finally gets it. They removed the requirement for hardware-assisted virtualization (HAV) from Windows Virtual PC, which means that XP Mode can be used on more computers. Many computers do not support HAV at all and others simply do not provide a method to enable it in the BIOS. The fact that you can use XP Mode now without HAV, will enable the use of these older (and sometimes newer) machines with XP-compatible applications that do not work on Windows 7.

In order to get the support for non-HAV Windows Virtual PC, you will need to download and install Windows Virtual PC itself and then download and install the update that removes the requirement for HAV. Both can be found here at Microsoft's website.

Windows 7 Batch Files – More of the Same

With every new release of Windows, the rumors start. "Windows 7 will destroy the command prompt," or "the command prompt will die in the next version of Windows." Of course, these rumors have never been true in the past and they are not true now. Windows 7 batch files work in the same basic way as batch files worked in Windows Vista, Windows XP and every NT-based system all the way back to Windows NT 3.1. Windows 7 batch files provide more of the same, but this is a good thing. You can use batch files for many tasks, including:

  • Information gathering
  • System configuration
  • Automation of administration
  • Simplification of redundant and mundane tasks
  • Just about anything else you can think of


Unlike the rumors, the truth is that Windows 7 batch files are more powerful than ever thanks to the introduction of new command line tools or commands in Windows 7. Here's just a sampling of the new tools that are included in Windows 7's command prompt:

  • PowerCfg – for power management configuration from the command prompt.
  • BCDEdit – OK, not new for 7, but who used Vista? This command is used to edit the boot configuration database.
  • TZUtil – for setting the timezone from the Windows 7 command prompt.
  • Defrag – a command line utility for full volume defragmentation (I still prefer CONTIG and Defraggler, but that's just me).


Additional tools were added or enhanced in the Windows 7 command prompt and are useful from within batch files. Traditional tools prove useful as well. For example, consider the following potential Windows 7 batch file:

@echo off
tasklist /FI "MEMUSAGE gt %1"

If you save the preceding text in a file named tbmem.bat, you can then run it as:

tbmem 10240

This command will then list any running processes using more than 10 MB (10240 KB) of memory. Instead of typing the full tasklist command, you can simply type the shortened batch file command. Windows 7 batch files can further shorten even more complex processes. I'm continually creating batch files that contain more than 20 lines. Now, if the exact same work were done outside of the batch file, I may be able to do it in less than 10 commands, but the batch files sure save me time over time.

This little post may get the gears turning again for some old timers (like myself) who used batch files in the good old DOS days and it may give some ideas to some GUI masters of the modern era. Either way, you should definitely take a fresh look at Windows 7 batch files to see where you can automate or improve your day-to-day work with the operating system.

Random Screening and Security

So, I just passed through security at the Columbus, Ohio airport for the sixth or seventh time this year. Of my journeys through the TSA stalls in Columbus, I recall one time this year that I was not selected for a little extra patting, rubbing or travel bag exploration. In my opinion, this is where the problem with random screening rests.

If the TSA would only scan boarding passes as the passengers go through security, they could determine which passengers have been selected for "random" screening many times in the past and ensure that they are not wasting their time on the same person again and again. For example, I have a friend who flies frequently (3-4 times each month like me) and he said he has not been "randomly" selected once this year.

The biggest problem is that we're depending on extremely biased machines to randomize the passengers. These biased machines are also known as humans. Maybe one TSA agent always selects the person they feel will be most cooperative. Maybe they select every fifth person through to attempt pure randomization. Through observation tests, I can assure you that no such pattern is used even if they are told to use such a pattern. In one sixty minute period I observed 53 passengers going through security. No humanly trackable pattern appeared in the selection process.

However, one interesting pattern did appear. Of the 53 people passing through, 7 were selected for additional screening. Of the 53 passengers, 4 helped other people with an item that fell or some other needed assistance. Not one of these four people were selected.

This made me so curious that I had to do an experiment. While sitting at the Atlanta airport, where hundreds trudge through security each hour, I was able to observe a security lane where the "random selector" agent could clearly see everyone as they were preparing to come through. In just over two hours, I observed 27 people helping someone else through the line. Again, they were not selected for additional screening.

Now, clearly, further research is required to verify this bias, but the preliminary counts seem to indicate that you can greatly increase your odds of avoiding "random" selection by helping someone on the way through the line. And this is just one example of the bias within the human machine.

So, how do we fix this. Simple, an alternating pattern must be used to select the "random" passengers. Each TSA agent can be assigned a pattern (one could be the 3, 5, 2, 1, 7, 3, 5, 2, etc and another be 4, 5, 2, 5, 3, 2, 1, 4, 5, 2, 5, etc) and the "random selector" agent can be replaced with another agent after 3-4 iterations of the pattern making it difficult for pattern watchers to discover the pattern.

Additionally, to add variety to the pattern, if a passenger has been screened more than 3 of the last 5 times they've flown within the last sixty days, the agent is notified through a vibration signal with a hip mounted device. The agent simply passes over this passenger and continues his pattern with the next passenger. Of course, this would require boarding pass scanning outside of security, but maybe this would provide some real value at the point of entry in opposition to what we have now.

Now, I know what you're thinking, "Tom, this sounds too confusing." I say that the TSA agents are paid very well and we should not hesitate to require this ability and skill from them. Those who can't cut it, simply find themselves in lower paid positions, such as the non-observing guard at the exit of security.

In the end, random just ain't random when humans are involved and it can actually make for weakened security. Just a thought.