Tp Link Archer C6 V320: Firmware Link

The firmware for the V3.20 version must be downloaded and updated manually, unlike newer versions like V4 which support cloud-based updates. [OpenWrt Wiki] TP-Link Archer C6 v3

Corrupted download or you forgot to extract the .bin from the .zip . Fix: Re-download the zip. Right-click > Extract All. Upload the .bin file only. tp link archer c6 v320 firmware link