Johnny Chin

How to remove Microsoft .NET Framework Assistant Extension from Firefox 3.0 and Firefox 3.5

I just upgraded to Firefox 3.5 and realized that Microsoft snuck in (spyware-like installation, without user acknowledgment) an extension to Firefox 3.0 that is not compatible with Firefox 3.5, that extension is the Microsoft .NET Framework Assistant 1.0.

Microsoft has released a newer version of that extension, version 1.1, which is compatible with Firefox 3.5. However, Firefox 3.5 cannot automatically update to it, you have to do it manually and can be found here:
https://addons.mozilla.org/en-US/firefox/addon/9449

Well … being that I want to use Firefox and stay away from Microsoft’s browser and plug-ins, I wanted to find a way to remove the Microsoft .NET Framework Assistant 1.0 extension, since you cannot just click “Uninstall” like all the other extensions I have in Firefox. Besides, why would I want to keep an extension installed that I did not install myself? Would you knowingly keep a piece of spyware running on your computer? Heck no!

So digging around, I found clues on how to remove it. Here is a script that I wrote to remove the extension from the computer and remove it from Firefox. However, I still had to manually remove the additional information Microsoft added to the Firefox UserAgent header.

@echo off
echo Removing dotNET Assistant Extension files …
rd /s “%windir%\Microsoft.NET\Framework\v3.5\Windows Presentation Foundation\DotNetAssistantExtension”
echo.
echo Removing dotNET extension from registry …
REG.EXE DELETE “HKLM\SOFTWARE\Mozilla\Firefox\Extensions” /v “{20a82645-c095-46ed-80e3-08825760534b}” /f
echo.
echo.
echo MUST manually remove the UserAgent setting from each Firefox profile …
echo.
echo you can manually delete this line from each prefs.js:
echo user_pref(“general.useragent.extra.microsoftdotnet”, “(.NET CLR 3.5.30729)”);
echo.
echo or do it from “about:config” within Firefox
echo.

However, this code did NOT work for all of my workstations. I found that in those cases I needed to manually remove an entry from the registry, so I created this .REG file:

REGEDIT4

[HKEY_LOCAL_MACHINE\SOFTWARE\Mozilla\Firefox\extensions]
“{20a82645-c095-46ed-80e3-08825760534b}”=-

Finally, to remove the added text from the UserAgent header in Firefox.

One way to do this is to simply open the prefs.js for your Firefox profile and remove the line which reads:

user_pref(“general.useragent.extra.microsoftdotnet”, “(.NET CLR 3.5.30729)”);

Or you can … in Firefox, type “about:config” into the URL box and you should see this:

Now in the filter box, type “useragent” and you should see something like this:

Right-click on the “general.useragent.extra.microsoftdotnet” line brings up a menu, select “Reset”.
Now close out of Firefox completely and restart it. You are now done.
 
 
Reference: http://support.microsoft.com/kb/963707