Hi there. I just installed the latest openwrt firmware on my TP Link WR940N. I deleted all the interfaces on it (wifi and lan) and now I have no idea how to connect to it...
Could you please help?

Generic Openwrt failsafe mode bypasses your network config:
http://wiki.openwrt.org/doc/howto/generic.failsafe

Router OFF The switch is behind a hole and require a paper clip or similar tool to, press it with router OFF, now power ON keep pressed until the SYS LED lights with the rapid-flash pattern.

(Last edited by danymarc on 8 Nov 2014, 20:44)

Didn't help. First of all I do not have the hole. I have small reset button but I believe that it is the same. What I did:
1) Turned off the router, removed the WAN cable. Pressed reset button and while holding it pressed power button. The system indicator started to blink. After some time (around 30 seconds) it stopped blinking but LED was on;
2) While the router is turned on, I pressed reset button and hold it for 20 seconds;
3) While the router is turned on, I pressed reset button then I turned the router of and while holding reset I turned it on.

I tried to connect by the cable and used all the ports (from 1 to 4). No effect ...

I also tried to ping 2 addresses: 192.168.0.1 and 192.168.1.1.

Any suggestions?

On my TL-MR3020, I get into failsafe mode by *repeatedly* (2Hz) pressing the reset button while the router is powering up.

Nothing happened

Entering failsafe mode may require several attempts, as there is only a 2-second window during the boot process when the button must be pressed, (and the exact time to push a button depends on the router, as the length of the boot process varies.). If failsafe is entered ok, typically the power led starts blinking rapidly.

And you must have the fixed IP address 192.168.1.x (2-253) on your PC, when you try telnet connection to 192.168.1.1.

You may also try pushing another button (wlan,wps, whatever). It does not need to be the reset button.

(Last edited by hnyman on 11 Nov 2014, 10:10)

I have 3 buttons on the router:
1) Power
2) WPS/RESET
3) Wireless On/Off

I tried to hold 1 and 2 both and separate while the router is on. I tried to hold them both and separate while the router booting. I tried to press them frequently while the router is booting. I tried to change IP on my PC to 192.168.1.111 and 192.168.0.111 (because before the problem I changed the routers' IP to 192.168.0.2 as I wanted to set up it as repeater). I couldn't get the PWR LED blinking....

I did not really understand you

not just WAN cable, ethernet too, no cables have to be connected to router when you press the right button, just power

(Last edited by danymarc on 12 Nov 2014, 01:16)

Ok. Removed all the cables (except power). And the only new effect I got was when I was rapidly pressing the reset button while router was booting. The effect was the SYS LED started to blink very rapidly. But what next? I am waiting and it doesn't stop blinking. I tried to connect LAN cable to LAN port (not WAN) and there is no effect. The LED that indicates that the cable is connected does not light on.
If I reboot the router and connect this cable then the LAN LED is working...

When the led is blinking very rapidly, you have entered the Openwrt failsafe mode. The router has network interface in 192.168.1.1, and has a telnet server running.

Like said in the failsafe wiki article, set the PC to a fixed IP address in 192.168.1.x (not 1), e.g. 192.168.1.2. Connect cable to a LAN port. And take telnet connection to the router (plain old telnet, NOT ssh).

After you have got the connection to the console, use the "firstboot" command to clear all your erroneous settings.

(Last edited by hnyman on 13 Nov 2014, 18:39)

I do not know why my post didn't appear here. I'll repeat. I finally got it working. You are right that it was failsafe, however there was 1 very special thing. I needed to put my cable not to LAN port but to WAN and only after that I was able to connect by telnet and do "firstboot".

Anyway thanks a lot, I finally got it working, now the only thing left to set-up is as repeater. And this is the new problem for me, but I hope I'll find good manual for that

@sdks if you are comfortable with CLI here https://forum.openwrt.org/viewtopic.php?id=39077
If not post it