If you are unable to connect your Smarther AC with Netatmo to the Internet: Turn off your thermostat at your electrical panel and then turn it back on and restart your Wifi/router. If this does not solve the problem and you have already configured your router manually, your router settings may be blocking the connection to the thermostat. In this case, please consult your router manual and follow these steps: Step 1: In your computer's Internet browser, enter the local address of your router, in the following format, http://192.168.xx (for example http://192.168.1.1). This can be seen in your router manual. Step 2: Sometimes a username and password are required. For most routers, this is "admin" and "admin". If not, refer to the manual. Step 3: You can now access the router configuration interface. Step 4: If you are using parental controls, check that you have authorized the thermostat. To do this, check if the MAC address (see: Where can I find the serial number of my Smarther with Netatmo connected thermostat?) is in the list of authorized devices. Step 5: If you are using a sleep function for your router, disable it. If you still cannot connect, follow these steps: Step 1: First, try assigning a fixed IP address to the thermostat by entering its MAC address in the "Where can I find the MAC address of my Smarther with Netatmo?" section. If you have an Android smartphone, you can also assign a fixed IP address to your smartphone. If necessary, there are tutorials to help you with this configuration: In the browser, type the brand and model of your router (Orange livebox for example). Then, type "Static IP for MAC address". Step 2: You can also open a specific port for the thermostat (Port No. 25050) in TCP so that it can communicate with the server. Step 3: Next, you can check the Wifi frequency band on your router. The thermostat does not work on the 5GHz frequency. Make sure that the 2.4 GHz mode is enabled. Step 4: If the Wifi channel has been changed manually, it may no longer allow an optimal connection. Check that the "automatic selection of the Wifi channel" mode is set to "1000 MHz". is enabled. Step 5: Finally, if your network has one or more extenders, make sure that each Wi-Fi access point has a different name (or SSID) and that the thermostat connects to the one with a strong signal.