In tip 0007 and tip 0215, I detailed the registry entries that control Autoplay in Windows NT.

These entries also work in Windows 2000, but an additional entry may also be used. If Autoplay is on for a CD-ROM changer, it will cycle all slots as you change media.

A Value Name of NoDriveTypeAutoRun, a REG_DWORD data type, can be configured to disable Autoplay on all drives of the specified types. NoDriveTypeAutoRun can be located at:

HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Policies\Explorer

HKEY_USERS\.DEFAULT\Software\Microsoft\Windows\CurrentVersion\Policies\Explorer

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Policies\Explorer

The data value to set is determinined by adding the following:

Value   Meaning                               0x1     Disables Autoplay on drives of unknown type.                               0x4     Disables Autoplay on removable drives.                               0x8     Disables Autoplay on fixed drives.                               0x10    Disables Autoplay on network drives.                               0x20    Disables Autoplay on CD-ROM drives.                               0x40    Disables Autoplay on RAM disks.                               0x80    Disables Autoplay on drives of unknown type.                               0xFF    Disables Autoplay on all types of drives. 
A data value of 0x95 is the default, which disables Autoplay on unknown drives, floppy drives, and network drives.

If Autorun is 0, Autoplay is disabled on all drives. If Autorun is 1, you can hold down the shift key as you change media to prevent Media Change Notification (MCN). Appropriate settings in NoDriveAutoRun also disable Autoplay.

When Autoplay is enabled it begins as soon as you insert media, so setup programs and music start immediately.

NOTE: If NoDriveAutoRun or NoDriveTypeAutoRun are set in the HKEY_LOCAL_MACHINE hive, then these setting in HKEY_USERS and HKEY_CURRENT_USER are ignored.

NOTE: If you set the NoDriveTypeAutoRun value via the Disable Autoplay Group Policy, you can add the CD-ROM drive type or disable Autoplay on all drive types. Any other settings must be done via the registry.