Hi,

I had just upgraded my TL-1043ND router to firmware WR1043ND_v1_130428 and noticed 2 things:
1. The router had reset its configuration back to factory defaults (default SSID, no WiFi password !)
2. I couldn't login to the router admin page using the default "admin"/"admin"

I usually use Firefox (currently version 21.0) for my browsing, and couldn't login.
No matter what user/password I entered, the login page remain unchanged: no "wrong password" or any feedback.
I noticed that the new login page seems more "fancy", so I thought that one of my Firefox addons caused the problem.
I have tried Firefox in Safe-Mode, but that didn't work either.

Finally, I tried Internet Explorer 8 (I am using Windows XP), and the login page now works OK.
I had managed to login to my router, and reconfigure it all over again.

I still don't know why Firefox cannot login to the new login page,
so I configured my IE-Tab plugin (in Firefox) to always open 192.168.1.1 using IE-Tab.

Uri

I was facing the same issue after reverting the openwrt firmware back to stock (V1_140319) and resetting: I could not login with admin/admin on 192.168.1.1 using Firefox on a Mac. However, as suggested by FreePix, I can login with admin/admin if I access the router on http://tplinklogin.net.

Gijsbert

I had the same problem after resetting an Archer C7 to factory defaults. Using Firefox on a Mac, the login page simply would not accept admin as username/password. It did not matter whether I used the URL 192,etc., or tplinkwifi-net (as specified by the manual), or tplinklogin.net. The login page came up but would not react to the admin/admin entries.

I did not try the IE tab plugin suggested by urim, as I do not have that installed.

What worked for me was to switch to Safari. The login worked on the first try.

There is something about Firefox that jinxed my many earlier attempts.