It is common for IE or Edge to pop up a window on your system after a reboot has happened, if you have changed the network. While this may seem like it is the work of a virus, like when you have Internet Explorer not responding, the pop-ups may be due to some default settings in Windows.
Windows has a component specifically meant to identify changes in network, called the “Network Connectivity Status Indicator” or NCSI. It performs the function of detecting the status of internet connectivity, and comes as a part of the NlaSvc service. One of the things it does is background testing, which can tell you if the machine is connected to the internet. NLA or Network location awareness works alongside NCSI, by finding out if the connection is in a domain or public network. This way, it can set up a proper firewall.
Windows 7 will show a message lasting a short time about you needing further actions to connect to the internet. This means you will not get internet until you open the browser and match the Wi-Fi hotspot requirements to log in. After this, the connection will be normal, and even the yellow-colored bang mark will disappear.
Recent Windows versions have made the user experience more comfortable for normal users, in that when the machine detects a login, it will open the browser window.
You may ask why pop ups come up from IE or Edge when you are in a company or corporate network, without any hotspots nearby. The simple reason is that there is a proxy connection at the office, and Windows is not able to connect to the NCSI website directly. In cases such as these, the proxy gets contacted in the background, and more often than not, this will require proxy authentication. The URL will redirect to the MSN portal.
It is seen that many anti viruses will block the URL, which leads to the taskbar showing limited access. Resolving this issue can be done in simple step – adding the msftncsi website to the list of trusted URLs.