This article tells how to arrange web browser plug-ins so that certain file types are opened by specific applications, with particular attention given to the QuickTime 3 for Windows plug-in.

The QuickTime 3 plug-in has no influence over the order in which Internet web browser plug-ins are loaded, nor does it affect the way Internet browsers assign MIME types. Additionally, the QuickTime 3 plug-in does not take priority over other plug-ins. When several plug-ins handle the same MIME type, only one of them will get priority over that mime type.

The Windows-based versions of Netscape Navigator and Netscape Communicator will load plug-ins based on the order they occur in the \Plugins directory. The first item to occur in the directory will load first, making it the lowest priority, the second item will be the second lowest priority, and so on. If the QuickTime plug-in occurs last, it will get priority over all of the MIME types it can open. You can use the "DIR" command from a DOS command prompt to determine the current directory order of the \Plugins directory. Do not use the order shown in Windows 95.

If you wish for another plug-in to open a given MIME type, it must occur in the \Plugins directory after the QuickTime plug-in. Begin by moving the entire contents of the \Plugins directory to another directory. Moving only a portion of the plug-ins out and back into the \Plugins directory, or reinstalling plug-ins using an installer is not a reliable method for changing the loading order.

Using Netscape Communicator 4.05, this example shows how you might configure LiveUpdate's Crescendo to open .MID files, Netscape's plug-ins to open .AU, .AIF, .AVI, and .WAV files, and QuickTime to open .MOV files along with any other remaining MIME types. Since QuickTime can open the same MIME types as Netscape's plug-ins, and Crescendo, it must be loaded first (lower priority). Netscape's LiveAudio and Crescendo can both open MIDI MIME types. Therefore, Crescendo (higher priority) must be moved after LiveAudio (middle priority).

This procedure requires three basic basic steps.
1. Quit Netscape.
2. Move the entire contents of the Netscape\Communicator\Program\Plugins directory to a different directory.
3. Move each of the plug-ins and its components back to the Netscape\Communicator\Program\Plugins directory, starting with the lowest priority, and ending with the highest.
It may be easier to print out a list of the installed plug-ins, and note which plug-ins can open the same MIME types, then prioritize the noted plug-ins.

Here is the order for this Example:

Plug-in	File Name
Netscape Default	npnul32.dll	<- lowest priority (first moved)
QuickTime	npqtplugin.dll
Netscape Audio Streaming	nplau32.dll
Netscape Sound Player	npaudio.dll
Netscape AVI	npavi.zip
Netscape AVI	npavi32.dll
LiveUpdate Crescendo	MPlayer (sub-directory)
LiveUpdate Crescendo	crestest.mid
LiveUpdate Crescendo	CresPlayer.class
LiveUpdate Crescendo	crestest.htm
LiveUpdate Crescendo	CresObserver.class
LiveUpdate Crescendo	DelsL1.isu
LiveUpdate Crescendo	Npmidi32.dll
LiveUpdate Crescendo	Sequence.dll
Cosmo Player	Cosmo (sub-directory)
Cosmo Player	npcosmop.dll
Cosmo Player	npcosmop.jar	<- highest priority (last moved)


Note: You can verify which plug-in is enabled for each MIME type by choosing About Plug-ins from the Help menu.

If you would like more refined control over MIME types and plug-ins, consider using one of the third party applications specifically designed to assign a MIME type to a particular plug-in.

For additional information on Netscape Navigator, or Netscape Communicator contact Netscape Communications Corporation.

For additional information on LiveUpdate's Crescendo contact LiveUpdate.

Copyright © 2000 Apple Computer, Inc. All rights reserved.