Note: The exact menu names may vary slightly between 2021 versions.
With the pandemic still raging in 2021, VoLTE and analog phone port stability became non-negotiable. Older firmware had a bug where the voice sub-system would crash after 72 hours of uptime. The 2021 update fixed the memory leak in the voice DSP.
If you followed the guide but the router is now bricked (all LEDs dark or only Power solid with no network), perform this emergency recovery: zte+f671y+firmware+update+2021
If this fails, contact your carrier for a warranty replacement – most F671Y units had a 3-year warranty from 2021.
Before diving into the 2021 firmware, let’s establish the baseline. Note: The exact menu names may vary slightly
The ZTE F671Y is a Category 4 LTE router typically locked to specific carriers (e.g., Telkomsel in Indonesia, Smart in the Philippines, or Ooredoo in the Middle East). It features:
By early 2021, many units were still shipping with firmware from late 2019 or early 2020. These older builds suffered from several known issues: If you followed the guide but the router
This set the stage for the 2021 firmware rollout.
In 2021, many carriers began refarming spectrum for 4G+. The F671Y required new band combination tables to lock onto carrier aggregation (CA) pairs like B3+B40 or B1+B8. Without the update, users experienced stuck connections at 4G only (non-CA), capping speeds at ~50 Mbps instead of the theoretical 150 Mbps.