I have an older TL-WA850RE model and I tried to update the firmware, as it had never been updated before. However, I later discovered that version 1.2 is not the same as 1.20... so I updated to the wrong firmware version.

I can still access the management page, but when I try to connect to a router, the connection is not established; only the Wi-Fi network name of the extender changes.

I tried updating the firmware again with the correct version, but the message "The update failed because the updated file version was incorrect. Check the file name." Error code 18005 appears. I tried with different file names, but none worked.

The firmware version that appears as installed is the one I specified above.

I would like to thank in advance anyone who can help me and save my extender from going to waste...