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I am trying to reinstall Silverlight plugin, but get an error messages that tells me that my system does not support 64bit version, I am running Vista64.

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My computer is an older quad-core intel based system, running Vista64 Ultimate. I have used Firefox for years, and have the latest version. Amazon.com Instant Video is asking me to install Silverlight which I have been trying to do but find that when I download the .exe file and run it I get an error message telling me that my operating system does not support 64bit (huh?) The Microsoft site has no obvious support for this download anywhere. What do I do?

My computer is an older quad-core intel based system, running Vista64 Ultimate. I have used Firefox for years, and have the latest version. Amazon.com Instant Video is asking me to install Silverlight which I have been trying to do but find that when I download the .exe file and run it I get an error message telling me that my operating system does not support 64bit (huh?) The Microsoft site has no obvious support for this download anywhere. What do I do?

All Replies (4)

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Hello there,

Unfortunately Win64 Firefox as of V41.0+ will only have the 64-bit Flash Player white listed currently and will not support Silverlight plugin anymore. https://support.mozilla.org/en-US/questions/1080439

Hope this helps!

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I don't know about SIlverlight 64-bit, but Firefox would need the 32-bit version of Silverlight. And when Mozilla does release the 64-bit Windows version it will be for Windows 7, 8.1, and Windows 10 - there won't be WinXP 64 and Vista 64 compatibility. And as Machine Master mentioned, only Flash 64 will be supported - no other plugins.

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You may have 64-bit Vista however you are running 32-bit Firefox (for Windows) so you need 32-bit Plugins for them to run on your Firefox. The WOW64 in your Firefox useragent shows it is a 32-bit application running on 64-bit Windows.

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Can you try installing the 32-bit version from this page:

https://www.microsoft.com/getsilverlight/Get-Started/Install/Default.aspx