First you should uninstall Teamviewer, if you hasn't done already. (‘Start’ –> ‘Settings’ –> ‘Control Panel’)

Step 2: Now you should click on the start, then in the "run command" type this %appdata% –> delete TeamViewer folder IF this just directs you to the AppData\Roaming BUT doesn't delete the TeamViewer folder in there, so delete it manually.
ALSO Make sure to delete it in “C:\\Program Files\\Teamviewer” as well.

Step 3: Now install teamviewer again, BUT remember when installing it to choose ‘For Personal Use’