Flashing an Archer c7 V2 with LEDE, Open-WRT or DD-WRT requires a process whihc enables recobery mode within the device prior to flashing. If attempts are made to flash without first getting into recovery mode and error will occur " Unable to Install- Firmware is not Signed" or "Not Signed Firmware cannot be flashed" Something to that effect.
You will need to read a few things and download others :-
https://mikepalmer.net/tp-link-archer-c7-ac1750-v2-tftp-recovery/
https://tftpd64.codeplex.com
LEDE Project software:-
https://lede-project.org/toh/views/toh_fwdownload?dataflt%5BBrand*%7E%5D=tp-link
https://lede-project.org/docs/targets/ar71xx
Open-WRT software:-
https://wiki.openwrt.org/toh/hwdata/tp-link/tp-link_archer_c7_ac1750
https://downloads.openwrt.org/chaos_calmer/15.05.1/ar71xx/generic/openwrt-15.05.1-ar71xx-generic-archer-c7-v1-squashfs-factory.bin
https://downloads.openwrt.org/chaos_calmer/15.05.1/ar71xx/generic/openwrt-15.05.1-ar71xx-generic-archer-c7-v1-squashfs-sysupgrade.bin
https://wikidevi.com/wiki/TP-LINK_Archer_C7_v1.x
DD-WRT :-
https://www.dd-wrt.com/wiki/index.php/TP_Link_Archer_C7
https://wiki.openwrt.org/toh/tp-link/archer-c5-c7-wdr7500#tftp_recovery_de-bricking
- ARCHER C7 V2, TP-LINK WNDR7500, TP-LINK C7 ARCHER, OPENWRT, NON SIGNED SOFTWARE ERROR
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