I've seen this before and it's a pain. Some flakiness in ADB I haven't been able to figure out.
1. Do you have antivirus and/or other rmalware scanners? Try turning them off.
2. Run these commands
<open task manager and kill adb.exe (or adb-windows.exe)>
2. Do you know what the Android SDK is? If so, make sure you are using the Modaco drivers and not the SDK ones.
3. Please send a screenie of your device manager showing the ADB driver. It's at the top, Android Phone, click to open then screenshot.
BTW, if you don't log on to XP as an adminstrator, a: congratulations, you're one of the few b: log on as administrator and try again.
Edited by simonta, 15 May 2011 - 08:39 PM.
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Apple? I'd rather eat my own kidneys!