Solutions are displayed which match your selected specification «Computer takes weird actions».
Make sure you selected all specifications which apply to you.
Install Malwarebytes Anti−Malware
Malwarebytes Anti-Malware (MBAM) is a free computer virus removal tool (that offers a premium plan, too). It is an anti-malware software that scans for, identifies the symptoms of computer virus (or malicious software), and removes different types of malicious software (adware, spyware, trojans). Also, it offers an easy-to-use interface and a short wait time for scans.
Download it from the official website, install it on your computer, click of the Scan Now button and wait for the treats to be eliminated.
MBAM also has a premium version which offers a full-time background 'Malware Protection' and Malicious Website Protection, and a shorter wait time for scans, which is not the case with the free version.
Note: Although MBAM automatically updates its database, you can also check for updates manually by clicking Update. For best results, it is recommended to install it and scan for viruses with it while you are in safe mode. If you don't know how to enter the safe mode, click here to learn more.