Try these steps in order:
- Update Windows
- Go to Settings > Windows Update > Check for updates.
- Install all available updates, then restart the PC.
- Update Office 2019
- Open Word or Excel.
- Go to File > Account.
- Under Product Information, select Update Options > Update Now.
- If Update Now is missing, select Enable Updates first.
- If the problem happens only on a wired connection
- This can be caused by an incompatible network card driver or the IPv4 Checksum Offload feature.
- First update the network card driver through Windows Update or from the network card manufacturer.
- 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.
- Select OK.
- Note: disabling adapter features may affect network behavior; if needed, reverse the change after testing.
- Use a wired connection temporarily if currently on Wi-Fi
- Plug in a wired Ethernet connection and try Office again.
- If Office apps show “stopped working” or still cannot update
- Uninstall and reinstall Office 2019.
- The uninstall troubleshooter can remove Office on Windows 10 or higher.
- Restart after uninstalling, then reinstall Office 2019.
There is no separate “turn on internet for Office” switch in the provided guidance. The supported fixes are updating Windows, updating Office, checking the network adapter driver/settings, trying a wired connection, and reinstalling Office if needed.