Downloaded Reader 9.4.0 recently. Ever since, I've had problems with programs failing to start up when called via PowerDesk or Explorer. The Task Manager tells me that PowerDesk, or the called program, are "not responding". After maybe 30-40 seconds, they respond and run OK. Testing, I have found that this behavior begins after I run a Reader search of multiple PDF files. Once I've done such a search, the problem remains, until I reboot. Upon attempting to shut down, XP finds two Acrobat processes running, and those have to be manually closed to permit the reboot. I speculate that those processes are somehow interfering with the startup of other programs via the file manager. But I don't know that, and I don't know what to do about this. What I do know is that using the multiple-file Search function in Reader precipitates this troubling, "not responding" behavior.