When you install a Microsoft Office 2000 service pack, update, or security update on your computer, you may be prompted to insert your Microsoft Office 2000 CD-ROM. This article discusses why Office 2000 service packs, updates, and security updates may require one or more of your Office 2000 CD-ROMs.

If you installed Microsoft Office 2000 by using a CD-ROM, you may be prompted to insert one or more of your original Office 2000 CD-ROMs when you install an Office 2000 service pack, update, or security update. You may receive an error message that is similar to the following:

Office 2000 service packs, updates, and security updates require access to one or more of your original Office 2000 CD-ROMs for the following reasons:

• Office 2000 service packs, updates, and security updates typically update unversioned files. Updating unversioned Office 2000 files always requires access to the original source media.
  
  When you update a versioned file, you cause unversioned files to be updated also. Unversioned files are updated because Microsoft Office service packs, updates, and security updates use the Microsoft Windows Installer feature level patching. When a feature is updated, unversioned files that are associated with that feature are updated also.
  
  For example:
  
  The Winword.exe file is a versioned file and is associated with the WORDFiles feature. When you update Winword.exe, you also update additional files that are associated with the WORDFiles feature. The unversioned Word.pip file is associated with the WORDFiles feature and is updated when Winword.exe is updated.
  
  Note Later versions of Microsoft Office service packs, updates, and security updates may update unversioned files, but may not require you to have your original CD-ROM. You may not be required to have your original CD-ROM because later versions of Office make use of the MsiFileHash table. Microsoft Windows Installer 2.0 reads the MsiFileHash table when an unversioned file is updated. If the table contains an entry for the unversioned file, your original source media may not be required. Microsoft Office 2000 setup does not include an MsiFileHash table because it is designed for Microsoft Windows Installer 1.0. Windows Installer 1.0 does not use this feature.
• The Microsoft Office 2000 setup process runs custom actions that load files from the original Office 2000 CD-ROM.

Additional Notes

• Windows Installer preserves the integrity of your Office 2000 installation by "melding" the service pack, the update, or the security update with your current installation of Office 2000. Because of the design of this feature, Office 2000 seamlessly uses the service pack, the update, or the security update files when you add, remove, or reinstall Office 2000 components later.
• To keep the size of the service packs, the updates, and the security updates as small as possible, if these packages determine that a file to be updated is a later version than the original version of the file that is included with Office 2000, the service pack, the update, or the security update recopies the original file from your Office 2000 CD-ROM and then updates the file. As a result, your files are correctly updated, regardless of the version that they were before you installed the service pack, the update, or the security update.
• If you are in an environment where the Office 2000 CD-ROM or source is not readily available (for example, if you are in an office where all the users installed Office 2000 by using a single CD-ROM and a multi-user license), you may have to contact your system administrator to obtain the CD-ROM or to access the source.
• If you purchased a computer where Office 2000 was preinstalled and you did not receive an Office 2000 CD-ROM with the computer, contact the company that sold you the computer (the original equipment manufacturer [OEM]) and then request a CD-ROM.

Office 2000 service packs, updates, and security updates may not require access to your original Office 2000 CD-ROM for the following reasons:

• You installed Office 2000 from a network location that contains a flat copy of Office 2000 and you have access to the flat copy on the network when you install the service pack, the update, or the security update.
  
  Note A flat copy of Office 2000 is a folder that contains the manually copied contents of the Office 2000 CD-ROMs.
• You installed Office 2000 from a flat copy that is stored on your computer's hard disk, and you have access to the flat copy computer's hard disk when you install the service pack, the update, or the security update.

Note If you installed Office 2000 from an administrative installation of Office 2000 that is stored on a network server, contact your system administrator for the appropriate method to use to update your system.