I've been using Microsoft Virtual PC product for many years, posting separate VPCs for each client's work and for test beds for installing beta software or trying out products for my Toolbox column. A couple of months ago I started noticing that when in a VPC the Tab and Esc keys were being ignored. For example, when I would use Alt+Tab from within a VPC I would be toggling through the applications in the host environment. Likewise, if I hit Ctrl+Esc from within a VPC it would display the Start menu options in the host environment. Because I try to use the mouse as infrequently as possible and stick to keyboard shortcuts, having a nonfunctional Tab key seriously hindered by productivity. From Alt+Tab to moving from one form field to the next to inventing code, it's amazing how frequently I use the Tab key.
My initial assumption was that there was some problem with Virtual PC. I found information noting such problems when using UK keyboards, but nothing specific to my problem. My research revealed that a general rule of thumb was to check for programs in the host environment that might be capturing keystrokes and thereby "stealing" the keystrokes from the VPC. My approach was rather ham-fisted, but what I did was the following: I launched task manager and started killing off processes one at a time. After each process was killed, I would go over to the VPC and see if it now recognized the Tab and Esc keys.
The culprit ended up being FogCreekCopilotHelper.exe. Copilot is a desktop sharing tool from Fog Creek Software that I use now and then when providing telephone-based consulting services. This process is supposed to shut down automatically when the Copilot software closes. However, sometimes it does not cleanly die off; instead, it lingers around and seems to swallow up the Tab and Esc keys in Virtual PC.
I first detected that FogCreekCopilotHelper.exe was the source of my problems several weeks ago, but I held off posting a blog entry because I wanted to observe how exactly this problem arose. I've had several sessions with Copilot where the FogCreekCopilotHelper.exe process shutdown cleanly and did not interfere with my Virtual PC experience. In the times when it has caused trouble I noticed that mid-way during the Copilot session the Tab and Esc keys stopped working in Copilot! The same behavior I noted in Virtual PC after the fact. And, sure enough, when Copilot loses the Tab and Esc keys the FogCreekCopilotHelper.exe process does not cleanly die, but rather sticks around and steals the Tab and Esc keys from Virtual PC.
Long story short, if you lose functionality for certain keys in Virtual PC first look for the FogCreekCopilotHelper.exe process and kill it if it's floating around. If you do not use Copilot (or if this process is not present) then start to systematically kill off processes until you find the troublemaker. This approach of methodically killing processes is not very elegant, but can help detect the problem assuming you do not inadvertently kill essential processes during the genocide.