Finally I took risk and upgraded my WR741ND with the latest firmware to date 130205. I did update 130205 straight away without installing any previous firmware first. Working fine so far..... :)

Thanks @Jeffrey This is my firmware: As you can see it is pretty old. On http://www.tp-link.us/support/download/?model=TL-WR741ND&version=V4 there is a warning as well: Also there is a clear warning...

Hussein, where are you from? Can you plz mention what is hardware version of your router?

Region : Others Model : TL-WR741ND Hardware Version : V4 Firmware Version : 3.12.11 Build 110914 Rel. 59688n ISP : PTCL I bought TP-Link TL-WR741ND Hardware version 4.21 with an FCC ID: TE7WR741NDV4....