That '''Search-Encrypt''' extension you have installed is known Malware virus, you need to get rid of it. See this: http://community.malwarefixes.com/main/topic/help-me-remove-search-encrypt/

As if you didn't already have enough homework... <p>Here's my suggested procedure for tracking down and cleaning up bad add-ons and other hijackers. I know it seems long, but it's really not that bad.</p> <p>(1) Open the Windows <strong>Control Panel</strong>, Uninstall a Program.</p> <p>After the list loads, click the "Installed on" column heading to group the infections, I mean, additions, by date. This can help in smoking out undisclosed bundle items that snuck in with some software you agreed to install. <em>Be suspicious of everything you do not recognize/remember, as malware often uses important or innocent sounding names to discourage you from removing it.</em></p> <p>Take out as much trash as possible here. If you're not sure, feel free to post program names or a screenshot of the list.</p> <p>(2) Open Firefox's <strong>Add-ons page</strong> using either:</p> <ul> <li>Ctrl+Shift+a (Mac: Command+Shift+a)</li> <li>"3-bar" menu button (or Tools menu) &gt; Add-ons</li> <li>in the Windows "Run" dialog, type or paste<br>firefox.exe "about:addons"</li> </ul> <p>In the left column, click <strong>Extensions</strong>. Then, if in doubt, disable (or Remove, if possible) unrecognized and unwanted extensions. <em>All extensions are optional; the troublemaker might not be obvious from its name.</em></p> <p>(3) You can search for remaining issues with the <strong>scanning/cleaning tools</strong> listed in this support article: [[Troubleshoot Firefox issues caused by malware]]. These on-demand scanners are free and take considerable time to run. If they finish quickly and especially if they require payment, you may have a serious infection. I suggest the specialized forums listed in the article in that case.</p> Hopefully that will flush anything on your system and in your Firefox that could be a problem.