I have a new Asus G1 laptop (Intel Core2DuoT7300 with 2 gigs of RAM) with Vista Home Premium (regularly updated) on it. I have a timer program that came with a 2007 version of QuickBooks Premium I bought at the end of last year and that I loaded onto the Asus this past summer after I got the Asus. The timer program is QuickBooks Pro Timer, ver. 8. The timer program looks like it did when I bought my first version of QuickBooks in 1997. I suspect Intuit has not substantially updated the program since then.

Anyway, after much trial and error, I found that the timer program, even running in XP SP2 compatibility mode under Vista, corrupts Windows Explorer after three to five hours of operation. The Windows digital time disappears from the lower righthand corner of the screen, the icons on the Windows task bar at the bottom of the screen begin to glow brightly, and eventually begin to disappear into the lower lefthand corner of the screen. If I let it go long enough, the restart/shutdown button accessed through the Windows "Start" button becomes unresponsive (although the "Sleep" button does not). Eventually, all the programs stop working and the system freezes. If I hit "alt-ctrl-del," the options screen for locking the computer, starting "Task Manager" and other tasks comes up. If I choose the restart option on that screen (the arrow on the red button in the lower righthand corner), I can restart the machine and the reboot removes the problems for a while (sometimes for less than three hours). If I wait too long, even that option will not work.

On occasion, by double clicking in the lower righthand corner where the digital clock used to be, Windows would respond by giving me a message that "Windows Explorer has stopped working" and that it was looking for a repair. Then it would restart Windows Explorer (without shutting down the programs) and things would go back to normal for a while (sometimes for less than two hours). That was the easiest fix, but I could not always get it to work.

I searched online for solutions for the problem under the "Windows Explorer has stopped working" error message but did not find anything like what I was experiencing. This happened on three different high-end Sony Vaio laptops (with Intel Core2Duo T7200 chips, 2 gigs of RAM and Windows Vista Business edition on them) that I bought and used, trading each one in under the warranty because of this problem over the course of three months. I finally gave up on the Vaios and took the Asus in trade (taking a loss of about $400). I thought the Sonys had a heat problem. Sony Repair could not duplicate the problem so it could not fix or diagnose it. None of the tech guys I showed the frozen screen to recognized it or knew what to do about it.

There are two other Vista laptops used by other folks in my workplace, neither of which experiences this problem, and neither of which has the timer program installed on it. Quickbooks offered no solutions and does not offer an upgrade of the timer. I finally stopped using the timer on the Vista for a day, keeping track of my time manually. The problem did not occur. The next day, I used the timer but turned it off when I did not need it running. The problem reappeared.

I now operate the timer on another laptop (with XP SP2 on it) and do not use it on the Vista laptop. That solved the problem. The XP machine runs the program without a hitch. I had used all of the programs I am using on the Vista on the XP machine for several months without a problem.

Vista owners should be aware that incompatible programs that run on Vista (so that you do not know they are incompatible) may cause Vista to freeze, even if you change the programs' "compatibility" settings. I hope this post helps someone else solve this problem without blaming the hardware, as I did, and without losing as much time as I did to the problem.