I bought a tv 9 or 10 (don't remember) license. As some of my partners upgraded, I am not able any more to connect with them. Also tv is messaging "suspect of commercial usage" .... YES I do commercial usage with tv 9, but I bought the license ! And also I cannot connect with people that upgraded the same product.
I think teamviewer is splitting it's own network of users (a commercial capital sin !) , a consequence of trying to sell licences as it upgrades versions.