Hi, the default Search Engine is always Google unless you change it.

This could be an issue caused by AdAware or Web Companion from Lavasoft. That could be bundled with some software you installed. Always use Custom install. That will not help if they do not tell you though.

You can look for a file named dsengine.js in these locations. You should only find channel-prefs.js in the "defaults\pref" location. Any file found here apart from channel-prefs.js is suspicious. You can check the content of the file in a text editor (use open with and do not double-click the file).

C:\Program Files\Mozilla Firefox\defaults\pref\ C:\Program Files (x86)\Mozilla Firefox\defaults\pref\

You can look for a file named dsengine.cfg in the main Firefox program folder.

C:\Program Files\Mozilla Firefox\ C:\Program Files (x86)\Mozilla Firefox\

Delete the dsengine.js and dsengine.cfg files when present.

Please use more than 1 scanner as each uses diff tech :

• https://support.mozilla.org/en-US/kb/troubleshoot-firefox-issues-caused-malware

Save your Report and google each before deleting anything as do not want to delete something you need, If need help :

• https://forums.malwarebytes.com/topic/9573-im-infected-what-do-i-do-now/

Post in only 1 forum, then wait.

Please let us know if this solved your issue or if need further assistance.

Please make your friends aware. If they uninstall Firefox or stop using it, they still have the code in their system, Thank You From Mozilla Firefox Support.

You still don't understand the problem! I know how to get rid of malware AFTER it has installed. What I don't understand is how FireFox ALLOWED it to install in the FIRST place! This is why you are failing!

It’s very sad, but many software downloaders/ installers will trick you into installing not only their program, but other programs as well.

You have heard of the fine print in shady contracts, right? Well, some installers you need to look at the itsy bitsy teeny weeny fine print.

You are thinking you are giving the installer permission to install the program you want by using the recommended option. But if you use the Manual Option Instead, you discover all kinds of stuff that you do not even know what it is or what it does.

From now on, everyone needs to Use The Manual Option to put a stop to this.

Note that these programs can also change browser/computer settings.

True, except it doesn't apply to me. I have two different anti-virus programs plus Windows Defender. Yahoo, Bing and Chromium never asked to be installed on my PC. They installed themselves and Firefox allowed these programs to change my settings. I had a Yahoo pop-up appear while I was playing a non-online game. Bing informed me that my search settings needed updating while I watched a news video on CNN. I can remove all traces of these programs by going into Firefox settings, and Windows programs etc ETC. But no one can explain to me how they installed themselves! Why does Firefox allow them to change my homepage and search engine with no input from me?

Bulletpond said

I can remove all traces of these programs by going into Firefox settings, and Windows programs etc ETC.

Hi Bulletpond, what did you remove in Firefox settings?

Firefox should ask you before changing your default search engine, or before you install/activate an add-on that changes your default search engine. Websites can't change your default search engine unless you download something from them.

When this problem occurred in the past:

• Did you determine whether an add-on was responsible?

• Did you determine that there was an autoconfig file, as described in the first reply?

I think before we could speculate on how an add-on or config file got installed, we would need to know what you found.

If you haven't recently, I suggest double-checking your extensions. You can view, disable, and often remove unwanted or unknown extensions on the Add-ons page. Either:

• Ctrl+Shift+a (Mac: Command+Shift+a)
• "3-bar" menu button (or Tools menu) > Add-ons
• type or paste about:addons in the address bar and press Enter/Return

In the left column of the Add-ons page, click Extensions.

Then cast a critical eye over the list on the right side. Any extensions Firefox installs for built-in features are hidden from this page, so everything listed here is your choice (and your responsibility) to manage. Anything search-related, or that you just do not remember installing or why? If in doubt, disable (or remove).

I also suggest cross-checking by date in the Windows Control Panel "Uninstall a Program." What I mean is:

After the list loads, click the "Installed on" column heading to group the infections, I mean, additions, by date. This can help surface undisclosed bundle items that snuck in with some software you agreed to install. These ride-along programs may include deceptively named re-installers that continuously restore deleted programs and settings.