Do you receive any errors or alerts?  

 

Does Webroot SecureAnywhere display an alert?

 

If you disable Webroot, does Silverlight install?

 

 

I just installed Silverlight on my Win7x64 box without any issues.

 

Are you downloading Silverlight from the Microsoft website?

 

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

 

 

 

 

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First make sure WSA is not blocking it. Try installing silverlight again.



Open WSA interface. Click on Utilities > System Control > Antimalware Tools > Start. Look for any process named silverlight or related to it. Allow them if they're blocked or monitored.



On the WSA interface, click on the gear icon beside PC Security. Look under the tabs Quarantine and Block/Allow files for anything related to silverlight. Allow them or restore them.

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