Outlook Email Not Connecting Via Home Network

Yes. A home network problem can stop Outlook from connecting.

Common network-related causes in the provided guidance include:

• No Internet or local network connectivity.
• Outlook being in Work Offline mode.
• A firewall on the network blocking connections to the mail server, including the outgoing SMTP server for POP or IMAP accounts.
• A network configuration issue on Windows, such as incompatible network card drivers or the IPv4 Checksum Offload feature.

Practical checks:

1. Confirm the device has Internet access by opening websites in a browser.
2. In Outlook, check that it is not set to Work Offline.
   • In classic Outlook, go to Send/Receive and select Work Offline to reconnect if it is enabled.
3. If Outlook shows Disconnected, test whether mail works in a browser. If web mail works, the mail server is likely fine and the issue is more likely on the device or network.
4. If the issue happens only on one wired home connection, update the network card drivers.
5. If the wired connection shows No Internet Access, test disabling IPv4 Checksum Offload:
   • Open Control Panel > View network connections.
   • Right-click the network adapter > Properties > Configure > Advanced.
   • Select IPv4 Checksum Offload and set it to Disable.
   • Select OK.
6. For POP or IMAP accounts, a home router or ISP firewall can block SMTP. In that case, an alternative SMTP server from the email provider or network administrator may be required.

If multiple people in the same Microsoft 365 organization are affected, an admin should also check Microsoft 365 service health.

References:

• I can't send or receive messages with Outlook for Mac | Microsoft Support
• Classic Outlook
• Can't sign in or activate Outlook and Microsoft 365 applications
• Fix Outlook connection problems for Microsoft 365 account