o365 programs not recognizing Jabber for tel: links

There are some caveats when it comes to integration with tel: and callto: links inside Office apps.

Office apps (Word, Excel, Outlook, PowerPoint) don’t always honor the Windows default for tel: / callto:. They sometimes force integration with Microsoft Teams, Skype for Business, or Lync.

Even if Jabber is set correctly in the registry, Office may redirect links to Edge or a Microsoft UC client. This is by design in some builds — Microsoft assumes Teams is the default calling app.

This is why you saw behavior like: first click opens Jabber, subsequent clicks open Edge → Office caches or overrides the handler…in the end you need to fight against Office’s tendency to prefer Teams/Skype for tel: links.

Suggested solutions that could potentially provide help in a corporate environment.

Confirm Jabber Version → Use the latest Cisco Jabber (14.1+), as earlier builds had issues with Windows 11 integration.

Set Defaults at OS Level → In Windows 11:

Go to Settings → Apps → Default apps → Choose defaults by protocol

Set TEL and CALLTO to Cisco Jabber.

Disable Office Overrides:

In Teams / Skype for Business clients, disable the option “Register as the default calling app” if present.

In registry, use DisabledProtocolHandlerRegistrations under HKEY_CURRENT_USER\Software\Microsoft\Office\<version>\Lync to stop Office apps from re-claiming the tel: handler.

Deploy via GPO/Intune → Push registry fixes enterprise-wide to keep Jabber as the handler.

Fallback → If deep Office integration is critical (e.g. “click-to-dial” directly in Outlook contacts), Cisco generally recommends using Webex App (which has more active development) instead of Jabber, since Microsoft has moved to tighter Teams integration.

My answers are voluntary and without guarantee!

Hope this will help you.