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HP Scanjet -  Resolving Scanner Quits Working When It Is Plug and Played by Windows and Is not Detected or Is Detected as an Unknown Device for the Scanjet 5200c, 6200c, and 6300c Series



Purpose
This document describes the problem seen with the HP 5200c, 6200c and 6300c series scanners that quit working on any computer system, in any operating system (OS), when connected to the Universal Serial Bus (USB) port on the scanner.
Before beginning
Before following any of the steps below, unplug all USB devices except the scanner from the computer system.
Symptoms
The HP Scanjet 5200c, 6200c, 6250c, 6300c, 6350c, or 6390c series scanner is working correctly until it is reinstalled and Windows plug and plays (PnP) it. Now the scanner will not work on any computer system when using the USB interface. The problem may occur when the scanner is installed on a new computer system with Microsoft(R) Windows XP pre-installed or when it is installed on an upgraded computer system.
The HP Scanjet scanner may not be listed in the Device Manager or it may be listed as an Unknown Device. If the scanner is not listed in the Device Manager or is listed as an Unknown Device, follow the steps in the "Solution" section of this document.
Complete the steps below to verify if the scanner is in the Device Manager as an Unknown Device:
Entering the Device Manager

   1.
      Open the System Properties window:
          *
            In Windows XP, click Start , right-click My Computer , and then click Properties. The System Properties box will open.
          *
            In Windows 2000, right-click My Computer , and then click Properties . The System Properties box will open.
   2.
      Click the Hardware tab, and then click Device Manager. The Device Manager will open.
   3.
      Click the plus sign (+) next to Unknown Device. A drop down menu is displayed. If there are no Unknown Devices, skip to Step 5.
   4.
      Unplug all USB devices and verify the Unknown Device has been removed. Plug the USB device back in, and verify it is present again. If it is present again, uninstall it. If it does not reappear, skip to the next section of this document.
          *
            In Windows 95, 98 and Me, select the entry for the Unknown Device, click Remove , and then click OK to remove the device.
          *
            In Windows 2000 and XP, right-click the unknown device and then click Uninstall .
   5.
      Plug and Play the device.
          *
            In Windows 95, 98 and Me, click Refresh . If the scanner now appears correctly, refer to HP support document Troubleshooting Initialization Errors and Other USB Connectivity Issues for more information. If the scanner does not appear or appears as an unknown device, continue with the remainder or this document.
          *
            In Windows 2000 and XP, click Action , and then click Scan for Hardware Changes . If the scanner now appears correctly, refer to HP support document Troubleshooting Initialization Errors and Other USB Connectivity Issues for more information. If the scanner does not appear or appears as an unknown device, continue with the remainder or this document.

Cause
It is believed the problem is caused when the Non-Volatile RAM (NVRAM) in the scanner becomes corrupted. This prevents the scanner from enumerating properly on the USB bus. The 6200c and 6300c scanners will continue to work correctly using the SCSI connection and the 5200c scanners will continue to work correctly using the parallel interface.
Solutions
CAUTION: 	When installing the Firmware/Connectivity Update, make certain that all USB devices except the scanner have been disconnected from the computer system
HP has developed a USB Connectivity/Firmware update for the HP Scanjet 5200c, 6200c, or 6300c series scanner where the NVRAM is corrupted. The update will rewrite the corrupted NVRAM information on the scanner, and then force the computer to restart, which should cause the scanner to redetect and install correctly.
	NOTE: 	This update is only for Windows 2000 Professional and Windows XP Home and Professional editions.
If the computer system does not have Windows 2000 or XP, the scanner can be taken to another computer that does have Windows 2000 or XP to install the update. Once the Firmware/Connectivity Update has been installed on the scanner, the scanner may then be put back on the original computer system and installed with no problems.
Step 1: Download and run the update

   1.
      From the driver downloads, software updates and patches Web page , type your scanner model (for example, Scanjet 6200c) in the search field and press Enter.
   2.
      Select your version of Windows and download the update:
   3.
      Scanjet 6300c, 6200c, and 5200c series USB Connectivity/Firmware Update.
   4.
      Follow the instructions on the download page to execute and install the update.
      	NOTE: 	Keep the firmware update saved on the computer in case it is needed in the future.

Known issues with the update
If the scanner is still not found after installing the update and restarting Windows, unplug the USB and power cables from the scanner, wait 20 seconds, and then plug the USB cable in first, followed by the power cable.
It may be necessary to remove the scanner from Device Manager if Windows lists it as an "Unknown Device." To remove the scanner from the Device Manager, follow the steps below:

   1.
      Open the System Properties window:
          *
            In Windows XP, click Start , right-click My Computer , and then click Properties. The System Properties box will open.
          *
            In Windows 2000, right-click My Computer , and then click Properties . The System Properties box will open.
   2.
      Click the Hardware tab, and then click Device Manager. The Device Manager will open.
   3.
      Click the plus sign (+) next to Imaging Devices. A drop down menu is displayed.
   4.
      Select the entry for the HP Scanjet scanner and/or Unknown Device, and then click Remove.
   5.
      Click OK to remove the device.
   6.
      Close the Device Manager window and then close the System Properties windows.
   7.
      Restart the computer system. New hardware should be found during the restart and the scanner drivers loaded.

Related troubleshooting documents available

    *
      HP Support document - HP Digital Imaging - Troubleshooting Initialization Errors and Other USB Connectivity Issues
    *
      HP Support document - HP Digital Imaging - General Troubleshooting for Initialization Errors and/or the HP Scanjet Scanner Stops Working
    *
      ? HP Support document - USB Scanner Quits Working, Scanner not Found or Scanner Could not Be Initialized Error Message, or Scanner Is Listed as an Unknown Device in Microsoft(R) Windows 95, 98, Me and XP