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DM8700 ends up in Boot Loop after Firmware Upgrade to 6.2.9

DM8700 will blink red or sometimes red and green after first reboot when firmware update completed.

01/02/2026

Details

Firmware Release 6.2.9 Boot-Loop Issue with Special USB Ports

Issue

After installing DMST 25.2.0, readers running firmware 6.2.9 may fail to complete startup and instead cycle in a boot loop.

Affected Devices

Any DataMan reader on firmware 6.2.9

Only when connected via USB to certain “special” ports (e.g. Dell PowerShare)

Cause

A compatibility issue between firmware 6.2.9 and the power-sharing characteristics of select USB ports prevents the reader from initializing correctly.

Workaround

  1. Disconnect the reader from the special USB port (e.g. Dell PowerShare). Such ports have a small battery symbol next to the socket.
  2. Reconnect the reader to a standard USB port on the same host.
  3. Power-cycle the reader; it should now boot normally.

Resolution

A fix is planned for an upcoming firmware revision. In the meantime, always use a regular USB port when working with firmware 6.2.9 readers.

Note: This behavior does not occur when the reader is powered via PoE or using supported USB ports.