Check your system, Is it updated or not. If it needs Updation, kindly do the same. Restart your router and reset all settings. Check DNS and IP addresses for routerlogin.net.
I am using Netgear Router, some days before it shows same problem. I did the same procedure. If you unable to connect kindly connect your router customer help centre.
If this is not fruitful to you, then I am really sorry. I only suggest you this because you didn't mention any info about router and about you PC. So, if you have Netgear router, then you can use this information. If Not then ignore the post.
First, make sure your laptop is 'not' connected to the modem/router via an Ethernet cable and follow the steps:
1. Go to "Control Panel".
2. Next go to "Network and Internet" and then "Network and Sharing".
3. Now click on "Manage Wireless Networks".
4. On this screen, remove all wireless connections by "right clicking" on it and select "Remove network" from the drop down menu.
5. After doing this, close the open windows and reboot the computer.
6. Once the computer is fully reloaded, scan for the "Wi-Fi networks".
7. Click on the available network that you want to access and select "connect".
8. It takes a moment, but then you will be asked to give a password for your Wi-Fi connection. Type in the password and click the "connect" button.
It should now be connected.
NOTE: If this doesn't work, you may want to reset your modem/router, and then once it is fully loaded again, repeat the above steps.
If this doesn't work, test seeing if your laptop will connect via Ethernet. If so, then your WiFi card may be going. You can either look to replace it/have it replaced, or get an external (plugs in via USB) WiFi card.