Follow the instructions in this post:
https://malwaretips....wser-redirect-virus/The title says it's targeted at browser redirects, but it's effective against the root cause, not just the symptoms.
All the tools are free, and you will remove 99% of whatever may be infecting your computer. I used this guide to completely clean a neighbor's laptop (never again!!) which took about two days, but your experience may be different.
Other tools I would recommend:
The article didn't mention Malwarebytes, or Spybot Search & Destroy, so I will:
https://www.malwarebytes.org/https://www.safer-networking.org/The free versions of these tools work as intended, the extra pay-for features aren't needed for a one-time cleaning.
Wise Registry Cleaner
Debate is still going on about the effectiveness of registry cleaners, and this one is at least effective, easy to use, and portable.
http://portableapps....try-cleaner-portableWise Registry Cleaner Portable is a registry cleaner and optimizer packaged as a portable app, so you can work on PCs on the go. It's freeware for personal and education use. Like many system utilities, this requires admin privileges to run.
Should I Remove It?
http://www.shouldire...oveit.com/index.aspxShould I Remove It? is a very simple but extremely powerful Windows application that helps users, both technical and non technical, decide what programs they should remove from their PC.
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Should I Remove It? simply scans your computer for all its' installed programs and then ranks what should be removed by leveraging the wisdom of the crowd (and of course our technical experts) to determine what should not be installed.
Remember to uninstall any of these tools after using them to do the job, because some of them are designed to run in the background to "protect" your system, but usually they just slow things down. The only thing of that nature that should be left running should be a good antivirus of your choice.