|Assuming you are, in fact, talking about a Windows machine, is it possible that the "My Documents" folder was moved to a removable drive? All my external drives (connected by USB) are given a drive letter by Windows, and it's possible to move "My Documents" to one of those drives.|
Another possibility is that the "H:\" drive (if it was a single partition on a physical drive) may have died. I've had many IDE drives go south over the years, some of which are no longer seen by Windows.
Correct me if I'm wrong, but as I understand it, Macs don't use drive letters like Windows does. I believe they use a similar convention to Linux/Unix. This is what leads me to believe you are referring to a Windows machine.
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