Hi there.
I am trying to install Openwrt to TL-MR3420 v5 but I couldn't manage to do that. I tried both "openwrt-18.06.0-ramips-mt76x8-tplink_tl-mr3420-v5-squashfs-tftp-recovery.bin" and "openwrt-18.06.1-ramips-mt76x8-tplink_tl-mr3420-v5-squashfs-tftp-recovery.bin" files* from the web GUI "firmware upgrade" section. But each time I try, it says "error code:4503 the uploaded file was not accepted."
*https://openwrt.org/toh/hwdata/tp-link/tp-link_tl-mr3420_v5
Please help me...