First, this is not a malware issue. I've scanned the computer in question multiple times. Situation is as follows: The machine boots normally. I then install ActivClient 6.2 on the machine. Typical install (custom install went no better). The install completes fine. No reboot is required. All ActivClient components work fine. I then install the drivers for a card reader. This goes just fine as well. No reboot required. I can then plug in my CAC card and go to my test sites. Everything works. When I reboot the machine, it gives a winlogon.exe error. Ok / Cancel are the only options. Clicking either, the machine bluescreens. When I uninstall ActivClient, it goes back to booting normally; no issues. Thinking it was my ActivClient install, I acquired a different install. Same results.