Help – Error 0x800704cf when signing in to Microsoft Apps on Desktop

Follow these steps in order, testing Outlook/Excel/OneDrive after each major step.

1. Confirm Windows sees an Internet connection
   • On the taskbar, check the network icon. If it shows “No Internet,” follow the Windows network troubleshooting first.
   • On the lock screen, select Network and make sure the device is actually connected to Wi‑Fi or Ethernet.
2. Verify basic Internet and DNS from Windows
   Open Command Prompt as administrator and run:
   • ipconfig to confirm the adapter has a valid IP address (not 169.254.x.x).
   • ping www.msn.com to confirm connectivity.
   • nslookup www.msn.com to confirm DNS resolution.
     If these fail, fix general network connectivity (router, ISP, Wi‑Fi/Ethernet) before focusing on Microsoft apps.
3. Check proxy settings (common cause for Microsoft apps only)
   If behind a corporate or school network, or if a proxy/VPN was configured, Microsoft apps may be blocked while browsers still work.
   • Open Control Panel → Internet Options → Connections → LAN settings.
   • If Use a proxy server for your LAN is checked, confirm it is correct with the network admin or temporarily clear it and test.
   • If a proxy is required, ensure Microsoft 365 endpoints are allowed through the proxy as described below.
4. Ensure Microsoft 365 endpoints are not blocked by firewall/proxy
   If a firewall or authentication proxy is in use, configure it to allow Microsoft 365 traffic. For example, allow outbound connections (TCP 80/443, HTTPS) to:
   • *.microsoftonline.com
   • *.microsoftonline-p.com
   • *.sharepoint.com
   • *.outlook.com
   • *.lync.com
   • osub.microsoft.com
     Also ensure the broader Microsoft 365 URLs and IP ranges are allowed as documented in the Microsoft 365 URLs and IP address ranges list.
5. Check Windows Network Connectivity Status Indicator (NCSI)
   If Windows incorrectly thinks there is no Internet, Microsoft 365 apps can fail sign‑in/activation even when browsing works.
   • Open PowerShell and run: Get-NetConnectionProfile
   • Check IPv4Connectivity. If it shows NoTraffic or LocalNetwork instead of Internet, NCSI is not registering Internet access.
   • Test HTTP probe URLs in a browser:
     • http://www.msftconnecttest.com/connecttest.txt
     • http://ipv6.msftconnecttest.com/connecttest.txt
       Both should return Microsoft Connect Test. If they do not, NCSI is misdetecting connectivity.
   If NCSI is not registering correctly, configure it to use GlobalDNS:
   • Run regedit.
   • Go to HKEY_LOCAL_MACHINE\SOFTWARE\Policies\Microsoft\Windows\Windows\NetworkConnectivityStatusIndicator.
   • Create a new DWORD (32‑bit) value named UseGlobalDNS and set it to 1.
   • Restart the device and test Microsoft apps again.
6. Repair corrupted Internet Settings profile
   A damaged Internet Settings “Connections” key can break app connectivity.
   • Back up the registry first (per Microsoft guidance).
   • Open regedit.
   • Navigate to HKEY_LOCAL_MACHINE/Software/Microsoft/Windows/ CurrentVersion/Internet Settings/Connections.
   • Right‑click Connections and select Rename.
   • Rename it to Connections.old.
   • Restart the device and test Outlook/Excel/OneDrive.
7. Disable IPv6 temporarily (test)
   Some environments have misconfigured IPv6 that affects Microsoft 365 apps.
   • Right‑click the network icon → Open Network & Internet Settings → Change adapter options.
   • Right‑click the active adapter → Properties.
   • Clear Internet Protocol Version 6 (TCP/IPv6).
   • Click OK, then test Microsoft apps.
   • If it works, re‑enable IPv6 later and investigate IPv6 configuration.
8. Ensure required Windows services are running
   • Press Start, type services.msc, open Services.
   • Confirm these services are Running:
     • Network Connected Devices Auto‑Setup
     • Network List Service
     • Network Location Awareness
     • Windows Event Log
   • If any are stopped, right‑click → Start.
   • If a service fails to start, open an elevated Command Prompt and run sfc /scannow, then restart and test again.
9. Check NIC driver and offload settings if only wired LAN is affected
   If Wi‑Fi works but Ethernet shows “No Internet Access” and Microsoft apps cannot sign in:
   • Update the network card driver from Windows Update or the NIC manufacturer’s site.
   • If still failing, disable IPv4 Checksum Offload temporarily:
     • Control Panel → View network connections.
     • Right‑click the adapter → Properties → Configure → Advanced.
     • Select IPv4 Checksum Offload → set to Disable → OK.
       Then test Outlook/Excel/OneDrive.
10. If all else fails
    If none of the above resolves the issue and only Microsoft apps are affected while general Internet works, a deeper Windows profile or OS corruption may be present. In similar cases, a full Office Online Repair or, as a last resort, an in‑place Windows repair/refresh has been required to restore Microsoft 365 connectivity.

References:

• How to troubleshoot non-browser apps that can't sign in to Microsoft 365, Azure, or Intune
• Microsoft 365 Apps activation network connection issues
• Can't sign in or activate Outlook and Microsoft 365 applications
• Troubleshoot Problems Signing In to Windows
• Microsoft 365 Apps activation error codes 0xCAA70007 and 0xCAA80000
• Sign in issues when activating Microsoft 365 Apps