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Microsoft technology used to program applications that can be accessed through a browser continued to be blocked for Firefox users Monday. Mozilla had been blocking two Microsoft plug-ins after the discovery that Microsoft's .Net 3.5 SP1 install silently adds a plug-in to Firefox allowing the surreptitious launch of a malicious AML browser application that could take over infected machines. One add-on, the Windows Presentation Foundation, aids programmers in developing applications using Microsoft technologies that can be accessed via a browser.
instead of just disable it, or want to get rid of the Java plugin, here is where they can be located. Launch regedit and they are at HKLM>Software>Mozilla>Firefox>Extensions. Back them up if you like, and to delete them just delete the keys located there for .NET and/or Java. I personally don't like the fact that EITHER company installed plugins without my permission, and deleted both on all my machines.