Huawei E5172 — Firmware Original
If you're looking for a specific version or having trouble with a carrier-locked device, I can help you find: The Steps to unlock the router for any SIM
Usually yes, but only if the carrier firmware is not "anti-rollback" protected. Try downgrading via TFTP. If it fails with "version list check error," you cannot downgrade. huawei e5172 firmware original