Troubleshooting

Troubleshooting

Start here when the strap is not visible, the connection fails, data does not move, or Windows blocks the normal app launch path.

Use this page for the shortest recovery path before diving into deeper protocol or transport investigation.

The Strap Does Not Show Up During Scan

Confirm the strap is being worn and the electrodes are wet.
Close Polar Beat, Polar Flow, and any other BLE client that might already own the connection.
Move the strap closer to the adapter and rescan.
Use the CLI scan path to confirm the problem is not only in the WPF surface:
```
dotnet run --project src/PolarH10.Cli -- scan
```

The Device Appears But Connect Fails

Run a direct connectivity check:

dotnet run --project src/PolarH10.Cli -- doctor --device <ADDRESS>

If Windows reports AccessDenied during service or characteristic access, see the Windows BLE note in Platform Guides.
Disconnect any other client that could still be holding the GATT session.

HR Connects But ECG Or ACC Never Starts Moving

Check whether PMD startup actually succeeded in the diagnostics log or protocol.jsonl.
Confirm notifications were enabled for the PMD control point and PMD data characteristic.
Retry with a fresh connection before assuming the strap firmware or decoder is wrong.

The Breathing Page Looks Wrong

Do not calibrate until ACC is already flowing.
If the chart moves but inhale and exhale are reversed, use Flip inhale/exhale instead of recalibrating.
If the status never becomes calibrated, rerun the full Breathing Workflow without touching the strap during the calibration window.

Coherence, HRV, Or Entropy Values Stay Unavailable

Coherence depends on accepted RR intervals, not just a heart-rate number. If RR is not clean yet, the coherence window can stay unavailable.
The HRV tab also depends on accepted RR intervals and, by default, a nearly full five-minute short-term RR window. A live heart-rate number alone is not enough.
A low-confidence or warming-up coherence state is expected until the RR window has enough stable coverage.
If the HRV tab stays on Warming up, keep the session running longer before treating it as a failure.
Breathing-dynamics entropy depends on successful breathing calibration plus enough accepted breaths after calibration.
If the breathing-dynamics plots stay flat at zero during warmup, that is expected until entropy becomes available.
Use Coherence Workflow, HRV Workflow, and Breathing Dynamics Workflow for the operator-side readiness checks.

Windows Blocks The Normal App Launch

On this machine, Windows application-control policy can block the normal multi-file .NET app launch path.

Use the canonical workspace build first:

powershell -ExecutionPolicy Bypass -File .\tools\app\Build-Workspace-App.ps1
.\out\workspace-app\PolarH10.App.exe

If Windows still blocks that multi-file workspace build, use the single-file publish workaround:

dotnet publish src/PolarH10.App/PolarH10.App.csproj `
  -c Release `
  -r win-x64 `
  -p:PublishSingleFile=true `
  -p:SelfContained=false `
  -o out/app-single

Then run:

.\out\app-single\PolarH10.App.exe

The Session Folder Exists But Looks Empty

Open session.json and check whether the sample counts are zero.
Inspect protocol.jsonl to see whether PMD start commands failed or the session stopped too early.
Record a longer test session so HR, ECG, and ACC each have time to populate.