Device doesn't connect to Wi−Fi (Windows phone)

Consider this as an option, especially if you reset your router and entered the same wireless network name (and password), but, before that, you were able to connect to that Wi-Fi network.

To "forget" the network, follow the steps below:

1. Go to Settings and tap on Wi-Fi;
2. Tap on advanced;
3. Tap and hold on the Wi-Fi network you want to forget and tap on delete;

After the Wi-Fi network is forgotten, reconnect to it.

Updating the operating system is a must, in order to improve the mobile device's functionality and eliminate bugs in the operating systems. Usually, the updates are being applied automatically, but sometimes this is not the case.

See the don't know how to update my device's operating system guide if you are not sure how to check for updates manually.