“Allow sites to ask to become default handlers for protocols”

Hello Louis Comolli,

For clicking phone numbers in Edge to trigger a call through Nextiva, make sure the tel: protocol is mapped to the Nextiva app in Windows. You can check this by going to Settings > Apps > Default Apps, scroll down and click Choose defaults by protocol, then find TEL and set it to your Nextiva app.

In Edge, also make sure the setting is enabled: go to edge://settings/content/protocolHandlers and confirm "Allow sites to ask to become default handlers for protocols" is turned on.

For anything beyond that — like how Nextiva handles incoming tel: links or its click-to-dial configuration — that would be best addressed by Nextiva's support, since it's their app that ultimately processes the call.

To let phone numbers in Microsoft Edge automatically open the Nextiva app (using a protocol like tel: or a custom Nextiva protocol), configure protocol handling in Edge and ensure the protocol is trusted/handled on Windows.

1. Make sure Nextiva is installed and registered as a handler for phone links
   • Install or repair the Nextiva softphone/desktop app.
   • During or after installation, ensure it registers itself as the default handler for tel: (or its own custom protocol, for example nextiva:). This is done by the app’s installer via Windows protocol registration.
   • If Nextiva has a setting like “Make this my default calling app” or “Handle click‑to‑dial links,” enable it.
2. Enable protocol handling in Edge for click‑to‑dial
   • In Edge, open Settings → Cookies and site permissions.
   • Look for Handlers or similar (this controls “Allow sites to ask to become default handlers for protocols”).
   • Turn on the option that allows sites to ask to handle protocols.
   • When a site tries to use tel: (or the Nextiva protocol), Edge will show a prompt asking whether to open the external app.
3. Use the external protocol dialog to remember the choice (managed environments)
   • If managed by an organization, admins can control the “Always allow this site to open links of this type” checkbox in the external protocol dialog using the ExternalProtocolDialogShowAlwaysOpenCheckbox policy.
   • When this policy is enabled, the user can select Always allow so future phone-number clicks open Nextiva without prompting.
   • Policy details (for admins):
     • Group Policy path: Administrative Templates/Microsoft Edge → Show an "Always open" checkbox in external protocol dialog.
     • Registry (Windows): HKEY_LOCAL_MACHINE\SOFTWARE\Policies\Microsoft\Edge → ExternalProtocolDialogShowAlwaysOpenCheckbox (REG_DWORD, 1 = enabled).
4. Test with a phone link
   • On a web page, click a phone number that is formatted as a link (for example, tel:+14255550146).
   • Edge should show an external protocol prompt offering to open Nextiva.
   • Choose Nextiva and, if available, check Always allow so future clicks dial automatically.

If the external protocol prompt never appears, the Nextiva app may not be correctly registered as a protocol handler on Windows; reinstalling or updating the app is required so Windows and Edge recognize it as the dialer.

References:

• ExternalProtocolDialogShowAlwaysOpenCheckbox
• Handle protocols in a PWA
• Default Programs
• Set Advanced Phone Integration options
• Managing trust options for Office Add-ins