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I'm getting "Firefox plug-in installation failed" from Microsoft. Saying my Windows is invalid. What do I do?

  • 3 replies
  • 3 have this problem
  • 4 views
  • Last reply by dumdidadida

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This is the mesage I'm getting after trying time and time again to download the add-on. It won't download.

Verify the successful installation of the Firefox plug-in

During a successful installation, the plug-in places two files on your system. To verify that these two files are present, do the following:

   Using Windows Explorer, locate the folder where you have installed your Firefox browser. For Firefox, the default location is C:\Program Files\Mozilla Firefox.
   Browse to the plugins folder under the install folder.
   Verify that the file npLegitCheckPlugin.dll is in this folder.
   Browse to the components folder under the install folder.
   Verify that nsILegitCheckPlugin.xpt file is in this folder.

If the files aren't there, try installing the plug-in again and then repeat these steps.

After the genuine Windows validation plug-in for Firefox has been installed correctly, retry Windows validation to run the test again.

This is the mesage I'm getting after trying time and time again to download the add-on. It won't download. Verify the successful installation of the Firefox plug-in During a successful installation, the plug-in places two files on your system. To verify that these two files are present, do the following: Using Windows Explorer, locate the folder where you have installed your Firefox browser. For Firefox, the default location is C:\Program Files\Mozilla Firefox. Browse to the plugins folder under the install folder. Verify that the file npLegitCheckPlugin.dll is in this folder. Browse to the components folder under the install folder. Verify that nsILegitCheckPlugin.xpt file is in this folder. If the files aren't there, try installing the plug-in again and then repeat these steps. After the genuine Windows validation plug-in for Firefox has been installed correctly, retry Windows validation to run the test again.

All Replies (3)

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Hi,

You can try to use IE Tab +. After installation, when on a problematic page, please try right-clicking > View Page in IE Tab + > Switch Rendering Engine, or View Page in Internet Explorer.

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I'm sorry if I should know what you're talking about, but I have no clue what you're saying.

I've tried downloading everything Microsoft is telling me to, but Firefox isn't downloading them and therefor, Microsoft is saying I don't have a valid Windows.

I've fallen in love with Firefox, but will switch back if this persists.

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IE Tab + embeds Microsoft Internet Explorer inside Firefox. So if the WGA plugin installation from Microsoft is failing, you can try the same validation through Internet Explorer.

You can also try using the Start Diagnostics and Resolve Now feature here through Firefox.

Validation error

Validate

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Modified by dumdidadida