There are many reasons for this problem; one of the reasons is that Windows Update failed to install or update the Network drivers, in that case, you have to update the required driver manually.

The "No Internet, secured" message on Windows computers means that you're connected to an internet signal, but it's not transferring data. There are a few ways to fix the "No internet, secured" ...

If your laptop loses internet connection when connected to an external monitor, you are not alone. While Wi-Fi problems are common, this could also be a glitch with the monitor or the laptop itself.