Users with Microsoft Windows Vista and an iPod might have encountered the problem that under certain circumstances the data on the iPod could become corrupted after removing it from the computer that was running Windows Vista. According to Microsoft the problem could arise under two circumstances which I pasted below:
- You use the Safely Remove Hardware feature in the notification area to disconnect the iPod. Then, you disconnect the USB cable.
- You use the Eject command in Windows Explorer to disconnect the iPod. Then, you disconnect the USB cable.
Both surely look like the normal way to remove an iPod from the PC, wonder if this did not happen if you simply removed the iPod without using the Safely Remove Hardware feature or the Eject command.
You can download two updates, one for the 32-bit version of Windows Vista (click for direct download) and one for the 64-bit version (click for direct download)
Found at the Pc Doctor.

Fix Do not Disconnect on Ipod