1) Turn it off then turn it on again
- First, check your Wi-Fi router and modem and make sure they are up and running.
- If you don't see the indicator lights working properly, or if something looks amiss, turn off or unplug your router.
- Turn your router back on and/or plug it back in, and wait a minute or two for the connection to reestablish.
- If you're still having problems with the Wi-Fi connection on your Chromebook, test out the connection on another device such as your smartphone, tablet, or smart TV.
Hopefully, that simple fix was enough to get you back on track. Still having problems, move on to step 2.
- Click (or tap) on the quick settings menu on the bottom right corner of your screen.
- Hover your mouse over the Wi-Fi indicator symbol to see if you're connected. If the indicator is shaded in full, then you should be connected. You may also see wording underneath indicating the signal strength (weak, medium, strong).
- Click on the drop-down arrow next to the Wi-Fi indicator to see which network you are connected to. It is possible your Chromebook is trying to join another weaker network that you don't want it to.
- Click on the Settings icon (looks like a gear) to explore further Wi-Fi settings.
- Click on Connected devices from the left navigation bar.
- Click on Forget to forget the network you're currently on. Repeat for any other networks that you see listed here.
- Close the Settings menu.
- Reopen the quick settings menu from step 1 above, and try to reconnect to Wi-Fi.
- Choose your network, reenter your login credentials, and rejoin.
3) Run diagnostics
If you've gone through all of the previous steps and still have issues, Chromebooks have a built-in Get Help app that can guide you through most known issues and how to solve them. Let's try that.
- Tap or click on the app launcher (or press the Google Assistant key).
- Open the Get Help app.
- Click on Getting online in the left navigation bar (has a Wi-Fi symbol next to it).
- Click on the Troubleshoot button.
- A window will pop up with information about your Wi-Fi connection. Click on the orange/red Run Diagnostics button at the bottom of the window.
- If everything checks out with green checkmarks, then you're good to go!
Source: Android Central
Hopefully, you were able to diagnose your Chromebook Wi-Fi issues and get back to running online smoothly and speedily!