The arcane nature of the registry strikes again! Things like this are controlled by binary entries in the registry, which everyone is scared to death of. Someday, someone very, very smart will write a utility that safely lifts the veil of registry obscurity. Until then, just the change of one bit can cause havoc.
It would be the same if it was all in text files. But the Registry is not what caused this. Instead, over the years I have found when ever the taskbar does not auto hide like it is suppose to, there is some application wanting attention some where thats preventing the taskbar from hiding.
....and my machine is only a month old!! Maybe I should complain to HP for a fix.
But if logicearth is correct (and I suspect he or she is correct), then there is nothing wrong with your system, and nothing to complain to HP about. The Taskbar is being prevented from hiding because there is an application on your system that is somehow related to the Taskbar, (e.g. perhaps it is one of the apps in your System Tray), and that app needs attention. That is what is preventing the Taskbar from hiding. Once you close that app or do the task it requires, the Taskbar should once again be able to hide.
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