Hi,
I've just got a Wr840n v3, sadly it's only 4M flash and 32M ram as it's the V3 of the product.
I tried to install LEDE but get the error below:
Error code: 18005
Upgrade unsuccessfully because the version of the upgraded file was incorrect. Please check the file name.
I know it's about tp-link locking down the firmware flashing process, many topics about this but none about this specific router. Could you help me getting ride of it and flash LEDE ?
You should read the 4/32 warning. And the 32 MB RAM is the more serious trouble than small flash.
https://lede-project.org/meta/infobox/432_warning
LEDE may not be stable for you 4/32 device.
Might be better to stock with OEM firmware or Openwrt 15.05.x (that has smaller older kernel).
So, I think that you are going to waste effort in trying to unlock the device.
(If you search the forum for 18005, it reveals that using bootloader TFTP flashing might the best option to overcoming locking. But I am not familiar with TP-link locking, so this is just based on 30 seconds casual search)
The image for going from factory to LEDE is 3.75MB...
https://lede-project.org/toh/views/toh_fwdownload
Item # 1056
You might try using TFTP instead of the TP-Link web gui.
TFTP tutorials…
I returned the device back to the seller, looking for some more powerfull device (I have some linux packages I would like to be able to install)
to fix this error you need:
setup a tftpd on ip 192.168.0.66
copy the openwrt-18.06.1-ar71xx-tiny-tl-wr840n-v3-squashfs-factory.bin
rename as wr840nv3_en_tp_recovery.bin on the tftp root.
hold the reset/WPS key and turn on this device