I just saw that teamviewer host was installed on our personal computer on 5/4/17. We have no knowledge of this. Why would this have happened and does it mean that someone has accessed our computer?
closed as too broad by techraf, Steve, Xander, Rory Alsop♦ May 8 '17 at 21:53
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TeamViewer is a program that provides remote access functionality, and often has a range of legitimate uses. However, it is also commonly used in a range cyber crime activity.
An attacker may have installed TeamViewer onto your machine either by using other malware, or persuading another user to install it themselves through social engineering. They may then attempt to access your machine through TeamViewer, and potentially install malware, search for financial information, or perform other malicious actions.
I recommend you check the TeamViewer logs to see if anyone logged into your machine using it. Then, you should uninstall TeamViewer if you do not require the software, and scan your computer for malware.
See here for an example of a 2016 scam affecting customers of the UK telecommunications provider TalkTalk, which used TeamViewer.