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Netscape-Style Plug-ins Do Not Work After Upgrading Internet Explorer
The information in this article applies to:
Microsoft Internet Explorer 5.5 for Windows NT 4.0 SP 2
Microsoft Internet Explorer 5.5 for Windows Millennium Edition SP 2
Microsoft Internet Explorer 5.5 for Windows 98 Second Edition SP 2
Microsoft Internet Explorer 5.5 for Windows 98 SP 2
Microsoft Internet Explorer 5.5 for Windows 95 SP 2
Microsoft Internet Explorer 5.5 for Windows 2000 SP 2
Microsoft Internet Explorer version 6 for Windows 98
Microsoft Internet Explorer version 6 for Windows 98 Second Edition
Microsoft Internet Explorer version 6 for Windows Millennium Edition
Microsoft Internet Explorer version 6 for Windows NT 4.0
Microsoft Internet Explorer version 6 for Windows 2000
Microsoft Internet Explorer version 6 for Windows XP
Microsoft Internet Explorer version 6 for Windows XP 64-Bit Edition

This article was previously published under Q303401
SYMPTOMS
Netscape-style plug-ins do not work after you upgrade Internet Explorer by installing any of the products that are listed above.

Some examples of Netscape-style plug-ins include QuickTime by Apple Computer, Inc.; Finale MusicViewer by Coda Music Technology; and AlternaTIFF by Medical Informatics Engineering.
CAUSE
The versions of Internet Explorer that are listed above do not support Netscape-style plug-ins.
RESOLUTION
Contact the manufacturer of your Netscape-style plug-in to inquire whether the manufacturer has a version of the component available that is built on ActiveX technologies. Apple has provided an ActiveX control that restores the QuickTime plug-in for Internet Explorer versions 5.5 SP2 and 6. Please visit the following Apple Web site to download and install this control:
http://www.apple.com/quicktime/

Developer information about the QuickTime ActiveX plug-in by Apple Computer, Inc. is available at the following Apple Web site:
http://developer.apple.com/quicktime/compatibility.html

STATUS
This behavior is by design.
MORE INFORMATION
The Internet Explorer versions that are listed above continue to support the Embed and Object tags and ActiveX. Content creators can continue to use the Embed tag for components that are built on ActiveX technologies, as has been the case since Internet Explorer 3. A few examples are the Flash and Shockwave products from Macromedia, as well as SVG Viewer from Adobe Systems. For additional information about the Embed and Object tags and ActiveX, please see the following Microsoft Web sites:
http://msdn.microsoft.com/library/de...ects/embed.asp

http://msdn.microsoft.com/library/de...ivex/intro.asp

http://activex.microsoft.com/activex/activex/

http://msdn.microsoft.com/workshop/a...cts/OBJECT.asp

http://msdn.microsoft.com/workshop/a...ects/EMBED.asp

The third-party products that are discussed in this article are manufactured by companies that are independent of Microsoft. Microsoft makes no warranty, implied or otherwise, regarding the performance or reliability of these products.