My previous exploration of Vista service packs and hotfixes led nowhere close to fixing my Vista issues. I was a little dejected for a while. But now I may have something to go on.
Excel 2007 just locked up on me today, as did Outlook. Recognizing the symptoms of an incipient total freeze-up of the system, I went in to take a look at the Task Manager. This once, I caught the conditions early enough that I was able to launch it and do some exploration. I quickly found a svchost process that was consuming a fair percentage of CPU (around 33%), and more troubling was also consuming memory—as I watched and investigated, it climbed from around 33 MB to over 60 MB.
I ran tasklist to see what that svchost process was running (svchost can run multiple services), but couldn’t figure out which process was the problem one. I found that if I right clicked on the process on the Process tab and chose Services, it would take me to the first service in the list that was running in that process. I then sorted the list of services by PID, opened a command prompt, and started net stopping the services owned by that PID systematically.
I found a few surprises; for instance, if you stop the uxsms process, which is responsible for the window manager, your screen goes totally black—but still accepts keyboard input. I was able to type in net start uxsms and bring back up the window manager. But none of the services I stopped fixed the climbing memory consumption, until I hit pcasvc, which is a service that is provided for compatibility with older versions of Windows. When I stopped the service, the memory usage stopped climbing and fell back, and I was able to do a clean reboot—though my Excel session never recovered.
A search indicates that other users have trouble with the same svchost process, though they indicate other culprits (ReadyBoost is one that gets mentioned). So there may be something going on here.
Update: Further testing indicates another possible culprit, which I disabled at the same time: CSCService, which supports Offline Files. It now appears pcasvc is OK. We’ll see if disabling CSCService does the trick.