The CD-ROM, DVD-ROM, or CD-RW drive disappears from My Computer, has a warning mark in Device Manager, or will not recognize recordable media due to Microsoft Media player corrupting the registry. In some cases the system may stop during the booting process with the error message " STOP 0x0000007b INACCESSIBLE_BOOT_DEVICE".

Microsoft Media Player 8 and 9 have the potential to corrupt the registry where the IDE lower filter loading order is determined. Normally the registry corruption is harmless. A number of circumstances can cause this defect to manifest as a serious issue. Typical actions that can expose this problem are:

• Automatic update of Media Player from Microsoft's Web Site
• Installation of recording programs i.e. (Nero Burning ROM, Roxio CD Creator, Lenovo Rescue and Recovery)
• Installation of block storage drivers i.e. (Digital Cameras, USB storage)
• Installation of autoplay handlers i.e. (PowerDVD, WinDVD Platinum)
• Installation of network attached storage managers (ISAM, i-SCSI)
• Installation of new CD hardware i.e. (Adding a second CD or DVD-ROM)
  
  

Any of the following systems running Microsoft Windows NT 4.0, Windows 2000, or Windows XP, configured with Microsoft Media Player 8.x or 9.x:

• 3000 J100 (type 8253, 8254, 8255, 8256, 8454, 8455, 8456, 8457)
• 3000 J105 (type 8258, 8259, 8459)
  
  
• NetVista (type 2169, 2179, 2254, 2255, 2256, 2257, 2259, 2273, 2275, 2283, 2289, 2292, 6043, 6049, 6266, 6270, 6274, 6276, 6279, 6286, 6290, 6336, 6337, 6339, 6341, 6342, 6343, 6346, 6347, 6348, 6349, 6350, 6596, 6643, 6644, 6645, 6646, 6790, 6791, 6792, 6793, 6794, 6795, 6822, 6823, 6824, 6825, 6826, 6832, 6833, 6838, 6842, 6843, 6844, 6848, 6881, 8181, 8182, 8301, 8303, 8304, 8305, 8306, 8307, 8308, 8309, 8310, 8311, 8312, 8313, 8314, 8315, 8317, 8318, 8319)

• ThinkCentre A30 (type 2296, 8191, 8198, 8199, 8316, 8434)
• ThinkCentre A50 (type 8084, 8085, 8089, 8090, 8126, 8147, 8148, 8149, 8174, 8175, 8176, 8177, 8178, 8320, 8419)
• ThinkCentre A50p (type 8192, 8193, 8194, 8195, 8196, 8197, 8432, 8433)
• ThinkCentre A51 (type 8105, 8107, 8109, 8117, 8119, 8121, 8122, 8123, 8124, 8129, 8131, 8132, 8133, 8134, 8135, 8136, 8137, 8138, 8424, 8425, 9212)
• ThinkCentre A51p (type 8420, 8421, 8422, 8423, 8427)
• ThinkCentre A52 (type 8153, 8154, 8155, 8156, 8157, 8158, 8159, 8160, 8161, 8162, 8163, 8164, 8165, 8166, 8167, 8168, 8169, 8170, 8287, 8288, 8289, 8296, 8297, 8298, 8326, 8327, 8328, 8329, 8340, 8341, 8342, 8343, 8344, 8380, 8381, 8382, 8782, 8783, 8784, 8785, 8786, 8788)
• ThinkCentre E50 (type 8290, 8291, 8292, 8293, 8294, 8295, 8469, 8472, 8473, 8474, 8708, 8709, 8710, 8711, 8719, 8771, 8772, 8773, 8774, 8776, 8777, 8778, 8779, 8817, 8818, 8819, 9214, 9215, 9216, 9217, 9218, 9219)
• ThinkCentre E51 (type 8463, 8464, 8465, 8466, 8467, 8468, 8712, 8713, 8714, 8715)
• ThinkCentre M50 (type 8128, 8185, 8186, 8187, 8188, 8189, 8190, 8413, 8414, 8415 8430, 8431)
• ThinkCentre M50e (type 8179)
• ThinkCentre M51 (type 8095, 8096, 8097, 8104, 8106, 8108, 8118, 8120, 8141, 8142, 8143, 8144, 8145, 8146)
• ThinkCentre M51e (type 9213)
• ThinkCentre M52 (type 8099, 8110, 8111, 8112, 8113, 8114, 8115, 8116, 8211, 8212, 8213, 8214, 8215, 9210, 9211)
• ThinkCentre M52e (type 8299)
• ThinkCentre S50 (type 8086, 8087, 8088, 8092, 8094, 8127, 8183, 8184, 8416, 8417, 8418, 8429)
• ThinkCentre S51 (type 8098, 8171, 8172, 8173)
  
• ThinkPad (type A30p, A31, A31p, G40, G41, R50e, R51, R52, R60, T40, T41, T41p, T42, T43, T43p, T60, X41, X40, X31, X30, X40, X41, X60)
• ThinkVantage Technologies (type Rescue and Recovery 2.x, Rescue and Recovery 3.x)
  
  

Attention: Using registry editor incorrectly can cause serious problems that may require you to reinstall your operating system. Use registry editor at your own risk.

For information about how to edit the registry, view the "Changing Keys And Values" online Help topic in the registry editor (regedit.exe) or the "Add and Delete Information in the Registry" and "Edit Registry Data" online Help topics in regedt32.exe.

Note: You should back up the registry before you edit it.

If the system is halted with a STOP 7b:

1. Start the system from CD or rescue diskette
   
2. Select 'Command prompt' from the recovery menu
   
3. Change directory to c:\winnt (for Windows 2000) or c:\windows (for Windows XP)
   
4. Execute 'REG DELETE HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Class\{4D36E965-E325-11CE-BFC1-08002BE10318} /v LowerFilters' on the command line
   
5. Boot to Windows
   
6. Uninstall all CD recording related software, including Windows Media Player.
   
7. Reinstall all CD related software, with Windows Media Player as last item installed
   

If the System is booting to Windows:

1. Uninstall all CD recording related software, including Windows Media Player.
   
2. Run registry editor (regedit.exe) and delete the registry value found at
   HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Class\{4D36E965-E325-11CE-BFC1-08002BE10318} named "LowerFilters"
   
3. Reboot the system.
   
4. Reinstall all CD related software, with Windows Media Player as last item installed