Restoring a completely bricked TP-Link WR741ND router has been performed to revive a router, whose bootloader has been wiped clean from flash memory by an incorrectly chosen factory default firmware. Since the bootloader was missing, no TFTP methods could be used and the JTAG port of the router was not easily accessible.

The flash memory IC has been removed from the router and the bootloader written to it, re-soldered to the router and voila, it works. The procedure is not complicated apart from soldering operations. Two very handy open-source tools make the procedure extremely simple. Dangerous Prototypes Bus Pirate was used to connect to the flash IC using a simple breakout board or dead-bug method and in combination with Flashrom used to rewrite the bootloader partitions. Flashrom developers were very helpful and cooperative, fixing a few minor bugs and we made sure that Spansion S25FL032P is fully supported.

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The detailed instructions how to perform the procedure can be found on our FlashMemory wiki page.

According to TP-Link, such bricking happens if you try to upgrade firmware version 110825 directly to version 120320. In fact, you must first upgrade to 111130 and then proceed with upgrade to 120320.