from the openwrt wiki
Return to Factory Firmware
If you have accidentally flashed your V1 or V1.1 before realizing that the 5GHZ network card will not be supported, and want to return it to factory firmware, you can follow the following instructions (tested on V1.1, harvested from other tp-link device wikis)
The following instruction also works on V2
→ generic.uninstall
Warning!
This section describes actions that might damage your device or firmware. Proceed with care!
Obtain the factory firmware from the OEM:
http://www.tplink.com/en/support/downlo ... =Archer+C7
UNTESTED in case the file name of this firmware file does not contain the word "boot" in it, you can simply revert back to original firmware
in case the file name of this firmware file does contain the word "boot" in it, you need to cut off parts of the image file before flashing it:
An example of an image file with the word "boot" in it is ArcherC7v1_en_3_13_33_up_boot(130729).bin.
Cut the first 0x20200 (that is 131,584 = 257*512) Bytes from original firmware (not sure why 0x20200, as the bootloader partition is only 0x20000, but it works!):
dd if=orig.bin of=tplink.bin skip=257 bs=512
You should transfer the firmeware image to the /tmp folder and revert back to original firmware (if available you can flash the firmware via the webinterface as well):
Via the safer method using sysupgrade:
sysupgrade /tmp/tplink.bin
Or alternatively you can use the mtd method:
mtd -r write /tmp/tplink.bin firmware
https://wiki.openwrt.org/toh/tp-link/tl-wdr7500
If you want to revert back to stock TP-link firmware from custom firmware, most of the time you can not flash the TP-Link firmware directly from the official TP-Link website.
The reason for this is that most of the downloadable firmware from the TP-Link website contains a so called bootloader section in front of the actual firmware.
Normally when upgrading the official (not the custom) firmware this is fine of course, the official software on the router provided by TP-link takes the bootloader into account
and handles or uses it properly so that your device keeps working.
However the custom firmware, like OpenWrt Gargoyle and DD-wrt (and probably others) only suspect an firmware image that doesn't contain a bootloader
and try to flash this extra data in the place of the spot in the memory where the firmware goes. That simply doesn't fit, resulting in a router that does not want to start up anymore
Because it is sometimes hard to find out how to remove the correct section of the firmware or to find and execute those instructions at all, I decided to create an unofficial
TP-link firmware download page that has no boot loader part anymmore. This means that the image can be flashed without worrying if there is still a bootloader within the image or not.
On most custom firmware variations out there the image downloaded from here can be flashed trough the webinterface, however some versions (like DD-wrt) need some extra steps that
are explained on the DD-wrt website.
http://www.friedzombie.com/tplink-stripped-firmware/