I have just downloaded OS 14 on my Mac and updated my Microsoft Office Apps but now cant sign in - network error 2604

Question

Also it says there is a problem with connection and security certificates

Answer 1

Hi,

It sounds like the network error 2604 and the certificate warning are happening because your Mac or Office can’t verify Microsoft’s secure servers after the macOS 14 update. A few things you can try:

1. Check your Mac’s date and time and make sure it’s correct in System Settings.
2. Open Keychain Access, find any Microsoft certificates, and set them to “Always Trust,” then restart your Mac.
3. Sign out of your Office apps, quit them all, and then sign back in.
4. Make sure both macOS 14 and your Office apps are fully updated.
5. If you use a VPN or firewall, try temporarily disabling them in case they’re blocking Office from connecting.
6. If nothing else works, reinstalling Office usually fixes certificate issues.

These steps usually fix this kind of problem without too much hassle.

Answer 2

Hi Sally Bateson

Thank you for reaching out to Microsoft Q&A Forum and sharing your experience.

The error you described (network error 2604) together with certificate warnings may point to a local authentication or security configuration issue. Please try the following on your Mac:

• Ensure all Office apps are fully up to date
• Quit all Office applications
• Open Keychain Access, search for entries related to Microsoft, Office, or ADAL, remove those entries, then restart the Mac
• Go to System Settings > General > Date & Time and confirm "Set time and date automatically" is enabled
• If you are connected to a corporate firewall or VPN, temporarily disconnect and try signing in from a standard home or public network
• Go to System Settings > Network, select your active connection, open Proxies, and confirm no unexpected proxy settings are configured
• Open Word and sign in when prompted.

To help narrow this down further, please confirm:

• Which Office apps are affected (Word, Excel, PowerPoint, Outlook, or all Office apps).
• The exact Office version installed.
• The full error message text shown on screen.
• Whether sign‑in works for the same account at Office on the web.

Please let me know how things go on your side as your update can also assist others in the community who may be facing the same issue.

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