TL/DR at bottom
I had a teacher lose all her files when I accidentally deleted her domain profile from her local machine. All her stuff was saved locally and not on our server so it's all gone. I used Recuva to retrieve her files but some came back corrupt. I searched for 2 days for a program that would repair damaged or corrupt Microsoft Office documents and found one on Softonic.com. Big mistake. Apparently there was a piece added onto the program called default-search that installed as well. It has since made it so I cannot use any browser, I cannot access my imaging server or my spice server, and I can't even get connected to my exchange server. I'm screwed! Is there anyone that's felt with this virus before, and if so, how can I get rid of it? I've removed it from all my browsers, uninstalled it from Windows and scanned my computer with Sophos antivirus, but still can't connect to anything.
TL/DR: default-search virus has made my work computer almost useless. How can I remedy this?