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Missing Silverlight Plugin

  • 9 bhfreagra
  • 11 leis an bhfadhb seo
  • 12060 views
  • Freagra is déanaí ó jscher2000

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I want to watch Netflix and refuse to use a different Brwoser than Firefox. So Here's the problem: After correctly uninstalling silverlight and reinstalling it again, Netflix keeps giving me the notification that silverlight needs to be installed, although it is. I have uninstalled Firefox clean and installed it again. I went in the internet up and down and did everything, like the microsoft fixing tool, I checked if everything is up to date, I literally did everything! When I keep browsing for solution, I see that on some websites it advices me to check my addons -> Plugins and select silverlight. Now, I do remember seeing Silverlight there plenty times, but it isn't there anymore at all, it's completely missing! Please help me!

Réiteach roghnaithe

If the above doesn't help...

Firefox usually discovers Silverlight from a registry entry created by the Silverlight installer. That entry points to a file here -- can you check that the file exists:

c:\Program Files (x86)\Microsoft Silverlight\5.1.40728.0\npctrl.dll

If the file does not exist, the installation failed.


If it does exist at that location, there are a number possible reasons that Firefox might not find it:

One possible reason for an installed plugin not to apppear on the Add-ons page is if Firefox is set NOT to scan the registry for plugins. Another is that Firefox's settings file storing plugin data has become corrupted. Here are the steps to check those possibilities:

Confirm that Firefox is scanning the registry for plugins

Firefox finds the Silverlight plugin from a registry entry. Some users have the scanning turned off for some reason. Here's how to check and fix that:

(1) In a new tab, type or paste about:config in the address bar and press Enter. Click the button promising to be careful.

(2) In the filter box, type or paste scan and pause while the list is filtered

(3) If plugin.scan.plid.all is not set to its default value of true, double-click it to toggle it back to the default.

If you changed this setting, exit and restart Firefox to trigger another scan.

If you check the Add-ons page again, success?

If Firefox is set to scan but still does not find Silverlight and list it on the Add-ons page...

Remove Firefox's plugin registry file

Sometimes the pluginreg.dat file becomes corrupted. You can remove it and have Firefox re-scan for plugins. As a side effect, any plugins you have disabled on the Add-ons page probably will be re-enabled, so you'll need to go back to that page one more time.

Open your current Firefox settings (AKA Firefox profile) folder using either

  • "3-bar" menu button > "?" button > Troubleshooting Information
  • Help menu > Troubleshooting Information
  • type or paste about:support in the address bar and press Enter

In the first table on the page, click the "Show Folder" button to launch a new Windows Explorer window showing your settings files.

Leaving that window open, switch back to Firefox and Exit, either:

  • "3-bar" menu button > "power" button
  • File menu > Exit

Pause while Firefox finishes its cleanup, then rename pluginreg.dat to something like pluginreg.old

Start Firefox back up again. (If you want to restore your previous non-private session, use History > Restore Previous Session.)

When you return to the Add-ons page, is Silverlight finally there?

Read this answer in context 👍 3

All Replies (9)

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Did that already....

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Firefox is a 32 bit application, so you need a 32 bit version of Silverlight for Firefox.

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Réiteach Roghnaithe

If the above doesn't help...

Firefox usually discovers Silverlight from a registry entry created by the Silverlight installer. That entry points to a file here -- can you check that the file exists:

c:\Program Files (x86)\Microsoft Silverlight\5.1.40728.0\npctrl.dll

If the file does not exist, the installation failed.


If it does exist at that location, there are a number possible reasons that Firefox might not find it:

One possible reason for an installed plugin not to apppear on the Add-ons page is if Firefox is set NOT to scan the registry for plugins. Another is that Firefox's settings file storing plugin data has become corrupted. Here are the steps to check those possibilities:

Confirm that Firefox is scanning the registry for plugins

Firefox finds the Silverlight plugin from a registry entry. Some users have the scanning turned off for some reason. Here's how to check and fix that:

(1) In a new tab, type or paste about:config in the address bar and press Enter. Click the button promising to be careful.

(2) In the filter box, type or paste scan and pause while the list is filtered

(3) If plugin.scan.plid.all is not set to its default value of true, double-click it to toggle it back to the default.

If you changed this setting, exit and restart Firefox to trigger another scan.

If you check the Add-ons page again, success?

If Firefox is set to scan but still does not find Silverlight and list it on the Add-ons page...

Remove Firefox's plugin registry file

Sometimes the pluginreg.dat file becomes corrupted. You can remove it and have Firefox re-scan for plugins. As a side effect, any plugins you have disabled on the Add-ons page probably will be re-enabled, so you'll need to go back to that page one more time.

Open your current Firefox settings (AKA Firefox profile) folder using either

  • "3-bar" menu button > "?" button > Troubleshooting Information
  • Help menu > Troubleshooting Information
  • type or paste about:support in the address bar and press Enter

In the first table on the page, click the "Show Folder" button to launch a new Windows Explorer window showing your settings files.

Leaving that window open, switch back to Firefox and Exit, either:

  • "3-bar" menu button > "power" button
  • File menu > Exit

Pause while Firefox finishes its cleanup, then rename pluginreg.dat to something like pluginreg.old

Start Firefox back up again. (If you want to restore your previous non-private session, use History > Restore Previous Session.)

When you return to the Add-ons page, is Silverlight finally there?

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Hi I have a similar problem after downloading Silverlight, I double click on the downloaded file to extract it, but get the error message extraction failed Access Denied.

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Hi hermanmarais, what OS/version are you running? Have you tried downloading Silverlight in a different browser to see whether you get the same result or a better result?

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Hi jscher2000, Thank you for your reply. I managed to get some guidance from Microsoft who indicted that Silverlight may have become corrupted and they send me solution. Anyway I have been able to install Silverlight.

My next issue is that for work we use a older website that requires Silverlight, I can access the website thought IE but really would like to use Firefox and get away from IE. The problem is that the website don't want to load. I get to the homepage and then try to log in. After entering the username and password it just get stuck and does not want to go any further. No error messages or anything.

With IE I had to activate compatibility view to allow the website to be fully functional. Is there something similar I can do in Firefox?

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hermanmarais said

With IE I had to activate compatibility view to allow the website to be fully functional. Is there something similar I can do in Firefox?

IE's Compatibility View modifies some newer IE behaviors to work more like older IE behaviors. Firefox doesn't have any internal option to work more like any version of IE, so unfortunately, no.