Phone Link initiates iPhone calls, but Transfer to PC fails and Bluetooth HFP audio endpoints never activate

Question

I have already submitted this issue through Windows Feedback Hub. I am posting it here to determine whether other Windows 11 and iPhone users are experiencing the same Bluetooth Hands-Free Profile call-transfer failure.

SYSTEM

Windows 11 Home

Version 25H2

OS Build 26200.8894

Phone:

Apple iPhone

Connection:

Microsoft Phone Link over Bluetooth

PROBLEM

Microsoft Phone Link connects successfully to the iPhone and can initiate a telephone call.

The iPhone successfully places the call, and Phone Link displays:

“Call on mobile device”

However, the call cannot be transferred to the PC. The “Transfer to PC” function does not successfully activate PC call audio, so the call remains on the iPhone.

IMPORTANT DEVICE MANAGER FINDINGS

Windows recognizes both expected iPhone Bluetooth audio profiles under Sound, video and game controllers:

• Paired iPhone A2DP SNK
• Paired iPhone Hands-Free HF Audio

Under Audio inputs and outputs, Device Manager also shows:

• Speakers (Paired iPhone Hands-Free HF Audio)
• Microphone (Paired iPhone Hands-Free HF Audio)

All relevant devices report:

“This device is working properly.”

HANDS-FREE DRIVER DETAILS

Driver Provider:

Microsoft

Driver Date:

2026-06-18

Driver Version:

10.0.26100.8737

Digital Signer:

Microsoft Windows

KEY FAILURE

Although the Hands-Free HF Audio devices appear in Device Manager, they do not appear as usable endpoints in the classic Windows Sound control panel.

The following device does not appear on the Playback tab:

• Paired iPhone Hands-Free HF Audio

The corresponding hands-free microphone does not appear on the Recording tab.

I enabled both:

• Show Disabled Devices
• Show Disconnected Devices

The hands-free playback and recording endpoints still did not appear.

LIVE CALL TEST

I started a real call using Phone Link and left the call active.

While the call was active, I opened the classic Sound control panel using:

mmsys.cpl

The Paired iPhone Hands-Free HF Audio playback device still did not appear.

Phone Link continued to show that the call was on the mobile device, and the call could not be transferred to the PC.

TROUBLESHOOTING ALREADY COMPLETED

• Removed and re-paired the iPhone and Windows PC
• Removed and reconnected the iPhone through Phone Link
• Restarted Windows
• Restarted the iPhone
• Reset or reinstalled Phone Link
• Updated the Intel Wireless Bluetooth driver
• Updated the Intel Wi-Fi driver
• Verified the external motherboard Bluetooth antenna
• Verified the Intel Bluetooth adapter in Device Manager
• Verified Microsoft Bluetooth Enumerator
• Verified Microsoft Bluetooth LE Enumerator
• Verified Bluetooth Device (RFCOMM Protocol TDI)
• Verified iPhone contact and notification-sharing permissions
• Tested Windows playback and recording device settings
• Enabled Show Disabled Devices
• Enabled Show Disconnected Devices
• Checked default communications device settings
• Checked exclusive-mode settings
• Tested during an actual live telephone call
• Confirmed that Windows is on Version 25H2, Build 26200.8894

WHAT IS WORKING

• Bluetooth pairing works
• Phone Link connects to the iPhone
• Contacts and notifications work
• Phone Link can initiate the telephone call
• The iPhone successfully places the call
• Windows detects the A2DP profile
• Windows detects the Hands-Free HF Audio profile
• The Microsoft Hands-Free Audio driver is installed
• Device Manager shows the hands-free speaker and microphone records

WHAT IS NOT WORKING

Windows does not expose or activate the iPhone’s Bluetooth Hands-Free HF Audio playback and recording endpoints in the Windows Sound subsystem.

As a result, Phone Link cannot transfer the live telephone call audio from the iPhone to the PC.

TECHNICAL ASSESSMENT

This appears to be a Windows / Microsoft Phone Link / Bluetooth Hands-Free Profile endpoint-activation problem.

Bluetooth itself is functioning, and the required HFP driver and device records are present. The failure occurs when Windows is expected to publish and activate those HFP endpoints for the live Phone Link call.

QUESTIONS

1. Is this a known issue with Windows 11 Version 25H2, Phone Link, and iPhone call transfer?
2. Are the Hands-Free HF Audio endpoints expected to appear only while the call has already transferred to the PC?
3. Is there a supported method to force Windows to rebuild or reactivate the Phone Link Bluetooth HFP playback and recording endpoints?
4. Is there a current Phone Link or Windows update that specifically addresses this issue?
5. Are any additional Windows services, optional features, Bluetooth components, or app packages required for iPhone call transfer?

I have attached a privacy-safe detailed troubleshooting report containing the complete test history.

Answer 1

CONFIDENTIAL — FOR MICROSOFT TECHNICAL REVIEW ONLY

MICROSOFT PHONE LINK WITH IPHONE LIVE INCOMING-CALL AND CALL-AUDIO TRANSFER FAILURE ENGINEERING ESCALATION REPORT — VERSION 2.0

CASE STATUS: UNRESOLVED — ESCALATION REQUIRED PRIMARY TEST DATE: July 26, 2026

1. ISSUE SUMMARY

Microsoft Phone Link successfully connects to an iPhone 16 Pro Max and synchronizes messages, contacts, and call history. Outgoing calls can also be initiated from the Windows PC.

However, two essential live-call functions consistently fail:

Incoming iPhone calls do not appear live on the PC.

Selecting “Transfer to PC” during a call does not transfer the call audio to Windows.

The iPhone rings normally, but Windows displays no incoming-call window, notification, ringtone, or answer/decline controls. After the call is missed, the missed-call record appears correctly in Phone Link.

During an outgoing call, Phone Link displays “Call on mobile device.” Selecting “Transfer to PC” does not complete the transfer. The call remains on the iPhone, and the iPhone Hands-Free playback and recording endpoints never become available in Windows.

SYSTEM CONFIGURATION

Operating system: Windows 11 Home, version 25H2 OS build: 26200.8894 Phone Link version: 1.26062.145.0 Mobile device: Apple iPhone 16 Pro Max Connection method: Bluetooth pairing and Microsoft Phone Link Bluetooth adapter: Intel Wireless Bluetooth Motherboard: ASUS ROG Strix X670E-E Gaming WiFi External antenna: ASUS Wi-Fi/Bluetooth antenna installed and connected Primary PC headset: Corsair VOID ELITE Wireless Gaming Headset Other audio tested: Sony TV/NVIDIA audio and standard Windows audio devices Microsoft Hands-Free Audio driver version: 10.0.26100.8737 Driver date: June 18, 2026 Driver status: Installed, enabled, digitally signed, and reporting no device error

Required outcome: Place and receive iPhone calls through the PC and use the PC headset, speakers, and microphone for the live call.

OBSERVED FAILURES

Incoming-call failure:

When another telephone calls the paired iPhone, the iPhone rings normally. Windows and Phone Link show no incoming-call interface, no ringtone, no toast notification, and no answer or decline controls.

This remains true even when Phone Link is open in the foreground on the Calls page.

After the caller disconnects, the missed-call entry appears promptly in Phone Link with the correct time. This confirms that post-call synchronization works while the live incoming-call event does not.

Outgoing-call audio-transfer failure:

Phone Link can initiate an outgoing call. The call starts on the iPhone, and Phone Link displays “Call on mobile device.”

Selecting “Transfer to PC” does not transfer the call. The call remains on the iPhone.

The iPhone Hands-Free playback and recording endpoints do not appear in the classic Windows Sound Playback or Recording panels, even during an active call and even when disabled and disconnected devices are displayed.

Bluetooth Hands-Free endpoint failure:

Device Manager recognizes iPhone Bluetooth profile records, including A2DP and Hands-Free Audio records. The Microsoft Hands-Free Audio driver loads without an error.

However, the corresponding live Hands-Free speaker and microphone endpoints are never published or activated in the Windows audio system.

Notification-registration concern:

Phone Link does not appear in Settings > System > Notifications under the Windows per-application notification list.

This may indicate incomplete or corrupted Phone Link notification or call-interface registration.

REPRODUCTION PROCEDURE

Pair the iPhone with Windows Bluetooth.

Connect the iPhone through Microsoft Phone Link.

Confirm that messages, contacts, and call history synchronize.

Open Phone Link and leave the application visible in the foreground.

From another telephone, call the paired iPhone.

Observe that the iPhone rings while Windows displays no incoming-call interface, notification, ringtone, or call controls.

Allow the call to become missed.

Observe that the missed-call entry then appears in Phone Link.

Use Phone Link to initiate an outgoing call.

When Phone Link displays “Call on mobile device,” select “Transfer to PC.”

Observe that the transfer does not complete and the call remains on the iPhone.

While the call is active, open the classic Windows Sound Playback and Recording panels.

Enable the display of disabled and disconnected devices.

Confirm that the iPhone Hands-Free playback and recording endpoints remain absent.

TROUBLESHOOTING COMPLETED

The following troubleshooting and validation steps were completed:

Confirmed that the ASUS Wi-Fi/Bluetooth antenna is installed and connected.

Confirmed that Intel Wireless Bluetooth is detected and operational.

Updated the Intel Bluetooth and Wi-Fi drivers.

Confirmed that the required Bluetooth services are running.

Removed the iPhone from Windows Bluetooth.

Removed the PC from the iPhone Bluetooth list.

Restarted both devices.

Completed a fresh Bluetooth pairing.

Reset Microsoft Phone Link.

Reinstalled Microsoft Phone Link.

Changed Phone Link background permission to Always.

Confirmed relevant iPhone sharing permissions and Phone Link access.

Removed and reinstalled the iPhone Hands-Free device records in Device Manager.

Confirmed that the Microsoft Hands-Free Audio driver is installed, enabled, signed, and reporting no device error.

Checked the classic Sound Playback and Recording panels with disabled and disconnected devices displayed.

Repeated endpoint checks during an active telephone call.

Tested outgoing calls initiated from Phone Link.

Tested incoming calls while Phone Link was open on the Calls page.

Tested PC audio through the Corsair headset, Sony TV output, and standard Windows audio devices.

Confirmed that post-call history synchronization continues to function after the live incoming-call failure.

The problem persists after all testing.

FUNCTIONS CONFIRMED OPERATIONAL

Bluetooth discovery and pairing work.

Phone Link connects to the iPhone.

Messages, contacts, and call history synchronize.

Outgoing calls can be initiated from the PC.

Missed-call records synchronize after the call ends.

Windows detects iPhone A2DP and Hands-Free Bluetooth profile records.

The Microsoft Hands-Free Audio driver loads successfully.

General PC audio output works.

The Corsair headset operates normally for other Windows audio.

FUNCTIONS THAT FAIL

Real-time incoming-call presentation in Phone Link.

Windows incoming-call notification and ringtone.

Incoming-call answer and decline controls.

Phone Link “Transfer to PC” call-audio handoff.

Activation and publication of the iPhone Hands-Free playback endpoint.

Activation and publication of the iPhone Hands-Free recording endpoint.

Phone Link registration in the Windows per-application notification list.

TECHNICAL ISOLATION

The evidence indicates that the failure occurs after Windows recognizes the iPhone and its Bluetooth Hands-Free Profile, but before Phone Link and the Windows audio engine activate and expose the live telephony event and two-way Hands-Free audio endpoints.

The Bluetooth hardware, external antenna, pairing process, synchronization channel, call-control path, iPhone Bluetooth profile records, and Microsoft Hands-Free Audio driver are operational.

The failure is isolated to the live incoming-call event path and the Hands-Free audio endpoint activation or publication stage.

ROOT-CAUSE ASSESSMENT

Most likely cause:

A Microsoft Phone Link or Windows Bluetooth Hands-Free Profile endpoint-activation defect. The Hands-Free profile and driver exist, but Windows does not complete the audio endpoint activation or publication process when Phone Link requests a call transfer.

Also highly likely:

A Phone Link live incoming-call event or interface-registration defect. The real-time ringing state is not surfaced on Windows, although the post-call missed-call record synchronizes successfully.

Plausible cause:

A compatibility regression involving Phone Link version 1.26062.145.0, Windows 11 build 26200.8894, and the current iPhone Bluetooth telephony implementation.

Plausible cause:

Corrupted or incomplete Phone Link notification or call-interface registration, consistent with Phone Link being absent from the Windows per-application notification list.

Less likely causes:

General Bluetooth hardware failure.

Missing or disconnected external Bluetooth antenna.

Intel Bluetooth driver failure.

Bluetooth pairing failure.

Corsair headset failure.

Incorrect Windows default-audio-device selection.

Missing iPhone sharing permissions.

These causes are considered less likely because the relevant components and functions have been independently confirmed as operational.

REQUESTED MICROSOFT ENGINEERING ACTION

Please investigate why Phone Link does not surface the iPhone real-time incoming-call event even though the subsequent missed-call record synchronizes correctly.

Please investigate why selecting “Transfer to PC” does not trigger the activation and publication of the iPhone Hands-Free playback and recording endpoints.

Please confirm whether this combination of Phone Link, Windows 11, the Microsoft Hands-Free Audio driver, and the iPhone is affected by a known regression.

Please provide a corrective update, supported workaround, registry repair, component-reset procedure, or diagnostic process that restores:

Live incoming-call presentation.

Incoming-call notifications and controls.

Two-way Hands-Free audio endpoint activation.

Successful transfer of live call audio to the PC.

Please clarify whether Phone Link should appear under Settings > System > Notifications and whether its absence indicates incomplete application registration.

Please advise which specific Microsoft diagnostic logs or traces should be collected if engineering requires further evidence.

CONFIDENTIALITY AND ATTACHMENT STATEMENT

This report is confidential and intended only for Microsoft technical review, troubleshooting, and engineering escalation.

No personal name is included.

No screenshots, recordings, exported logs, diagnostic packages, or additional attachments are included with this submission.

Any future evidence should be supplied only after Microsoft identifies the specific diagnostic material required and confirms an appropriate confidential submission channel.

FINAL STATUS

UNRESOLVED — SUITABLE FOR MICROSOFT ENGINEERING ESCALATION

The evidence demonstrates that the PC, Bluetooth adapter, external antenna, Phone Link pairing, synchronization services, call-control channel, iPhone Bluetooth profiles, Windows audio devices, and Microsoft Hands-Free Audio driver are operational.

The unresolved defect is the failure to surface the live incoming-call state and the failure to activate and expose the iPhone Hands-Free playback and recording endpoints when Phone Link requests a live call or transfer.

This is a focused and reproducible engineering issue rather than a general Bluetooth pairing, audio-device, or headset problem.

Answer 2

Hi Michael Nikou,

Based on the troubleshooting you've already completed, it appears the Bluetooth connection and Phone Link pairing are working as expected. Windows is detecting the iPhone's Hands-Free Profile (HFP) devices in Device Manager, but the corresponding audio endpoints are not being exposed to the Windows sound subsystem, which prevents call audio from transferring to the PC.

As an additional step, you could try the following:

1. During an active Phone Link call, open Settings > System > Sound > Volume mixer and check whether any temporary Phone Link or communications audio device appears.
2. In Device Manager, uninstall the entries related to Paired iPhone Hands-Free HF Audio under both Sound, video and game controllers and Audio inputs and outputs, then restart the PC and reconnect the iPhone to allow Windows to rebuild those audio endpoints.
3. If possible, test Phone Link calling with another Bluetooth-capable phone to determine whether the behavior is specific to the current iPhone pairing or affects HFP audio endpoint activation more broadly.

Since you've already submitted Feedback Hub diagnostics and performed extensive troubleshooting, this may require further investigation if the HFP endpoints continue to remain unavailable despite being detected by Windows.

Let me know if you need further assistance, feel free to ask me by clicking "Add Comment" or "Add Answer" if you cannot add comment so your response will be visible. Thanks for your effort.

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