Start with the first stage that failed. Discovery, matching, connection, operation, and workflow execution have different causes.
No device appears
- Confirm the hardware is powered and within range when using BLE.
- Confirm Bluetooth or USB access is enabled for the app and the device is visible to Android.
- For BLE, check the advertised name, service UUIDs, and manufacturer information.
- For USB, check the cable, port, vendor ID, product ID, and optional interface class.
- Confirm that the active profile has an identity matcher for the transport in use.
If the device is visible to the operating system but not in Dsync, the profile match is the next check.
A candidate appears but will not connect
- Confirm that the candidate uses the expected transport.
- Close another application that may hold the device connection.
- Check profile transport settings such as BLE connection parameters or USB baud and timeout values.
- Move closer to the device, retry once, and record the exact error if it fails again.
An operation is missing or has no effect
- Confirm that the operation exists under the expected component in the active profile.
- Check that the service and characteristic or USB channel are correct.
- Confirm that the operation’s read or write behavior matches the physical device protocol.
- For structured responses, check format, byte order, scale, and value units.
- Test the smallest safe operation before running the full workflow.
Do not repeatedly send a write command when the outcome is unknown. Confirm the device state first or ask the equipment owner for the approved retry procedure.
A workflow stops or saves the wrong result
- Check which step was last confirmed.
- Verify that the rule condition has the settings, telemetry, or context values it expects.
- Confirm that a poll has a reachable stop condition and a finite attempt limit.
- Check the operation response before saving it to a field record.
- Test the workflow with one known device and a controlled value.
What to send to support
Include the profile name and version, device model, transport, device state, operation or workflow name, approximate time, and exact error text. Do not include credentials, encryption secrets, or private payloads. 
