Last February or March (2010) I purchased very nice HP notebook PC for about $1,100: it’s a dvtt-2300 CTO Entertainment Notebook PC with a Mobile i7 Quad-core processor (720QM 1.6 GHz), 6 GB RAM, nVidia GeForce GT 320M graphics, and a 7,200 RPM 500 GB hard disk.
This unit also includes a USB-attached fingerprint scanner made by Validity Sensors, Inc. model VFS301. Ever since I bought this notebook, and despite several calls to HP Support early on after I’d purchased it, the fingerprint sensor has failed to “report in” every third time I start the machine up from a sleep or hibernation state. Following resumption of activity, the notebook would inform me on those occasions that it failed to detect the fingerprint scanner, and thus, that it could not be used. Every time, that is, until I installed the latest round of Patch Tuesday updates. Then the problem went away.
At first, I thought there might have been a driver update that snuck past me for the device. Nope. The driver date is 5/4/2009. Because it’s connected via USB, I next checked to see if any USB drivers had been updated. Nix: all those drivers predate the release date for Windows 7. Sleep and hibernation fall under the control of ACPI, so I checked to see if any of those drivers had changed, either. Nada. Same 6/21/2006 date as for USB (probably associated with Windows Vista).
So why did something that was working hit-or-miss all of a sudden start working without a hitch? It’s been 10 days now since the second round of updates for April hit that machine (released 4/26, updated on 4/27 on the dv6t) and not once has the fingerprint scanner gone missing at boot-up or upon wake-up from sleep mode. As far as I can tell, the only possible culprit is Update for Windows 7 (KB2492386) another of the legion of poorly documented (read the Knowledge Base article, if you think you can read between the lines better than I can) Application Compatibility Updates that Microsoft occasionally releases.
You’re probably wondering why I bothered to dig into something that fixed a problem rather than causing one. Surely, that’s reason for rejoicing, rather than investigation? I can’t help it, I’m terminally curious about what causes changes in the behavior of my systems. I’m just as intrigued (and a little bit piqued) to have a problem fixed mysteriously as I am to have a new problem show up on one or more of my systems. If anybody else has other ideas on what might have changed the fingerprint scanner from occasional bad boy to good to go, I’d sure like to hear them. Please comment!