OneDrive saying no internet connection

Can you go check your Windows Settings > Windows update, and see if you might have  KB5085516 available to install?

KB5085516 was released on March 21st to address Microsoft account sign in issue among some apps caused by KB5079473 https://support.microsoft.com/topic/march-21-2026-kb5085516-os-builds-26200-8039-and-26100-8039-out-of-band-09e85404-1cb6-4ed4-9ca5-3e40d74307b9

Follow these steps in order, based on what has already been tried:

1. Confirm OneDrive can sign in at account level
   • Open a browser and sign in to the Microsoft Account dashboard.
   • If sign-in fails there, use the help link on that page to fix account/password issues.
2. Check for known sign-in issues and update OneDrive
   • Make sure the latest OneDrive sync app is installed using the official Download link.
   • If sign-in still fails across PC, web, or mobile, there may be a broader connectivity or service issue.
3. Check firewall, VPN, and network filtering
   • Temporarily disconnect from any VPN.
   • Temporarily disable or relax any third‑party firewall or security software and test OneDrive sign‑in again.
   • Ensure the internet provider or network is not blocking Microsoft 365 endpoints. If using a work/school network, contact the network admin. For home internet, contact the ISP and confirm they allow access to Microsoft 365 services and OneDrive.
   • For detailed requirements, review the guidance in Required URLs and ports for OneDrive.
4. Reset OneDrive if an error code appears
   • If an error code such as 0x80040c81 or 0x8004de40 appears, follow the specific guidance:
     • 0x80040c81: This indicates difficulty connecting to the cloud. Reset OneDrive, then check the network connection (cable or Wi‑Fi) using the guidance under “How to fix your network connection” or “How to fix Wi‑Fi problems.”
     • 0x8004de40: Follow the dedicated article linked from the error codes page for sign‑in connection issues.
5. If OneDrive is stuck on “Processing changes” after sign‑in
   • Confirm the account is signed in (if the password was recently changed, sign in again).
   • Wait for resync if there were many changes or the connection is slow.
   • If it remains stuck, follow the “Unlink and re‑link OneDrive” procedure to fully reset the sync relationship.

If none of the above resolves the issue and the browser sign‑in works, but the sync app still reports no internet, the most likely causes are a local firewall/VPN/security product or ISP/network filtering that is blocking OneDrive-specific endpoints even though general browsing works.

References:

• Fixes or workarounds for recent issues in OneDrive
• Can't sign in to OneDrive
• What do the OneDrive error codes mean?
• OneDrive stuck on Processing changes
• Fix OneDrive sync issues on Windows 8.1 or Windows RT 8.1