While trying to copy files or folders from PC to an external USB storage devices such as USB flash drive, portable hard disk drive, memory card etc, Windows 7 might stop copying files anytime and displays an error message. Windows 7 stops copying the file or folder copy process before the process is done, and few times it stops responding as weel, forcing you to reboot your system to get it work normally. The cause of this issue might be the input/output (I/O) operations on the USB storage device, where the I/O operations fail.

It basically happens in Windows 7 or Windows Server 2008 R2 based operating systems that meets the following conditions :

• Has an NVIDIA USB Enhanced Host Controller Interface (EHCI) chipset
• Has at least 4GB of RAM

Microsoft Updates

This error is very annoying since it prevents the user from copying files from the computer to an external USB storage device. Since this problem is happening with many users, Microsoft team has released KB976972 updates as , which is capable of fixing the issue and resolving all errors.

“You encounter problems when you move data over USB from a Windows 7 or Windows Server 2008 R2-based computer that has an NVIDIA USB EHCI chipset and at least 4GB of RAM”, Microsoft says.

Download KB976972 Update for Windows 7 and Windows Server 2008 R2 – KB976972-x86.msu