Error code 18005

Issue: When trying to install a firmware image via TP-Link WebGUI, I get the following error:

Error code: 18005, Upgrade unsuccessfully because the version of the upgraded file was incorrect. Please check the file name.

Root cause: TP-Link “Region locked” firmware. This firmware is checking for a specific region signature when flashing.

Solutions:

1. Use an OpenWrt firmware image with the appropriate region code (US, EU, ...) for your device, if available
2. Make the filename shorter, like factory-eu.bin or firmware.bin
3. Use TFTP for flashing instead of WebGUI (TFTP flashing does not check regional code)
   https://community.tp-link.com/en/home/forum/topic/81462
   possibly rename the OpenWrt image to wr802nv1_tp_recovery.bin (adapt filename to your device)