You and the partner can both reboot your network routers and check if you can connect as intended.

Allow Full Access Control to TeamViewer.

But before you begin, make sure that your Windows and TeamViewer are updated to their latest stable versions. Partner did not connect to router TeamViewer error

There are various causes for this including the installation is faulty, incompatibility between the TeamViewer version installed on both the computers, etc. This error usually occurs when the Partner computer is not connected to a network, but it could occur even when they are connected to a network. One such error you may face is when TeamViewer is not able to connect – No connection to partner, Partner did not connect to router, Error Code WaitforConnectFailed. But at times, it is known o throws up errors. TeamViewer is a great remote assistance software that helps you access and control computers remotely. I have installed TeamViewer 10 in Ubuntu 14.04 and used it with mobile Internet (USB tethering).

Teamviewer please check your connection