I have same problem. Did you get help?
Running iTunes 6 on Windows XP set up for multiple users with each user having their own libraries and accounts with Apple creates problems when one user plugs their iPod into the PC if the other is logged into iTunes. The iPod is not recognized as a peripheral, does not show in the iTunes for the user who owns the plugged in iPod who has logged off briefly and simply shut down the other iTunes program - no iPod attached. The current user is faced with the do not disconnect icon on the iPod screen without being recogized by the iTunes software or the PC. How to resolve this multiple user dilemma and remove the iPod safely without the need for a reset?

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