IF YOU MAKE A WRONG INSTALL AND YOU CHOOSE COMPANY USE or IF YOU GET BLACKLISTED YOU CAN TRY THIS METHOD AND IT WORKS 100%
1. First close teamviewer, if it is running (u must close 2 running applications from task manager. hit ctrl+alt+del and close "teamviewer.exe" & "teamviewer_servise.exe"
2. Click on start -> Run -> type %appdata% -> delete TeamViewer folder
3. Delete registry folder: HKEY_LOCAL_MACHINE/SOFTWARE/TEAMVIEWER
& also delete HKEY_CURRENT_USER/SOFTWARE/TEAMVIEWER
(to access the registry go to Start->Run and type regedit and click ok)
4. Delete TeamViewer folder from Program Files
5. Change Mac Adress by right click on MyComputer -> Manage -> Device Manager -> Network Adappters -> Right click on your NIC, Choose Properties -> Advanced -> Click choose "Network Address" -> Type 12digit in Value box (Eg: 001A3F25454S) -> OK -> Disable and Enable your NIC in Network Connections. Now your MAC was changed.
6. Re setup TeamViewer and Enjoy it now.