Try these checks in order:
- Verify Windows sees the connection.
- Open Start > Settings > Network & Internet.
- Confirm Wi‑Fi is On and Airplane mode is Off.
- If the PC is on Wi‑Fi but Microsoft sign-in still says there is no internet, select Network on the lock screen and confirm the device is connected.
- Test whether the issue is only with Microsoft sign-in.
- If possible, check whether general internet access works on the PC.
- If the Wi‑Fi signal is weak, connect directly to the router or modem with an Ethernet cable.
- If using Ethernet, unplug and reinsert the cable so it clicks fully into place.
- Check the same network on another device to confirm the network itself is working.
- Try signing in another way.
- On the sign-in screen, use a password instead of PIN or biometric sign-in if available.
- Safe Mode sign-in only supports a password; PIN and biometric options are unavailable there.
- Start in Safe Mode with Networking if sign-in still fails.
- On the sign-in screen, hold Shift and select Power > Restart.
- Go to Troubleshoot > Advanced options > Startup Settings > Restart.
- After restart, select 5 or press F5 for Safe Mode with Networking.
- If sign-in works there, the problem is less likely to be caused by basic device drivers or default settings.
- If Microsoft 365 apps such as Outlook are affected mainly on a wired connection:
- Update the network card drivers through Windows Update or the network card manufacturer’s support/download page.
- If that does not help, open Control Panel > View network connections.
- Right-click the network adapter, select Properties > Configure > Advanced.
- Select IPv4 Checksum Offload and set it to Disable, then select OK.
- This can be a temporary workaround.
- If OneDrive or Microsoft 365 apps still cannot sign in:
- Confirm the correct account password by signing in to the Microsoft account dashboard.
- Make sure the latest version of OneDrive is installed.
- Firewall, VPN, or internet provider configuration can also block sign-in.