One common mistake most people commit while installing Teamviewer on their system is that, they forget to select the option ‘For Personal Use’ and instead install with the default option ‘For Commercial Use’. As a result teamviewer stops functioning after a couple of days from installation. Even though you are genuinely using it for personal use you’ll no longer be able to use Teamviewer.
Here’s a solution to fix this problem :
1> First uninstall the copy of Teamviewer from your system. This can be done with free uninstallers or by using Window’s default ‘Add or remove‘ program which can be found at: ‘Start’ –> ‘Settings’ –> ‘Control Panel’
2> Click on Start –> Run –> type %appdata% –> delete TeamViewer folder and also delete “C:\\Program Files\\Teamviewer”
3> Delete registry folder: hkcu/software/teamviewer and hklm/software/teamviewer
4> Refer to this tutorial to change the MAC Address: http://www.irongeek.com/i.php?page=security/changemac
5> Clean your systems registry – you can use a free registry cleaner for this purpose-http://www.eusing.com/free_registry_cleaner/registry_cleaner.htm
6> Once you have completely wiped out Teamviewer out of your system – install a fresh copy of Teamviewer. Ensure you select the option ‘Personal Use’ (I’m assuming that you are playing fair here) !