Does this problem occur with all searches or only one-word searches?

The One-Word Search Issue

When you enter a single word in the address bar (whether it's puppies or mozilla.org) and tap "Go" Firefox will first check whether it is a valid web server name. Some DNS service providers do not tell the truth and instead serve a page of search results.

If that is the situation, check the results page for an opt-out option. If you do not have one, you could try changing your DNS service provider (for example, in your wifi router settings on a network you control), or get used to tapping the Google icon in the drop-down that appears while you are tapping out your query.

I'm not aware of a way to force one-word queries to go through a search engine, although someone might have developed one.

If you meant you have this problem on Windows instead of Android, it's the same issue, but you might also check whether any extensions are overriding your normal search provider.

You can review and disable extensions on the Add-ons page. Either:

• Ctrl+Shift+a
• "3-bar" menu button (or Tools menu) > Add-ons

In the left column, click Extensions. The name of the problem extension may not be obvious...

Also for Windows, you may need to uninstall a program named Fast Search. More information on that in this article: http://malwaretips.com/blogs/surf-canyon-removal/

When you're in the Windows Control Panel using either Uninstall a Program or Add/Remove Programs, click the "Installed on" column heading to group items by date. This may help uncover undisclosed and unwanted programs bundled with something free you installed.