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Silverlight plugin won't install: error 1603... disable your antivirus

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  • 35 have this problem
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  • Last reply by Buddahfan

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I could not install MS Silverlight. I had to turn off my antivirus and try again and then it worked.

When I tried to install Silverlight it got to 99% complete then I got a generic error 1603 "installation failed" message that was no help. The silverlightMSI file in %temp% (run from command line) shows a 1406 error code because the installer was unable to modify a registry key for Firefox (HKEY_LOCAL_MACHINE\SOFTWARE\MozillaPlugins\@Microsoft.com/NpCtrl,version=1.0). I do have admin rights for my account but my stupid McAfee antivirus blocked the installer from modifying the key.

I could not install MS Silverlight. I had to turn off my antivirus and try again and then it worked. When I tried to install Silverlight it got to 99% complete then I got a generic error 1603 "installation failed" message that was no help. The silverlightMSI file in %temp% (run from command line) shows a 1406 error code because the installer was unable to modify a registry key for Firefox (HKEY_LOCAL_MACHINE\SOFTWARE\MozillaPlugins\@Microsoft.com/NpCtrl,version=1.0). I do have admin rights for my account but my stupid McAfee antivirus blocked the installer from modifying the key.

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1603 is a "Fatal Error"

Have a look at these two links to see if they are any help

I scanned both URLs using Virus Total and they are indicated as 100% clean.

A MSFT Support web page

Windows Installer error 1406 occurs when installing software

http://support.microsoft.com/kb/300451

and here at

BrightHub.com

Having trouble getting Silverlight installed on your computer? There are several things that you can do to troubleshoot Silverlight to get it to work correctly. For the most part, when Silverlight won't install it can be due to Windows files, browsers, and other software. Read more...

http://www.brighthub.com/computing/windows-platform/articles/62189.aspx

Modified by Buddahfan